Tuesday, January 12, 2021

Introduction of KOVAR parts

KOVAR parts are commonly used as metal casing materials in the electronic packaging industry. Because they have a linear expansion coefficient close to that of molybdenum group glass, and can produce less sealing stress during the sealing (melting) process with molybdenum group glass, so To obtain good air-tightness, in order to make the metal tube and shell to achieve air-tight sealing, in the entire sealing process, the annealing process undoubtedly plays an important role as a link between the previous and the next. The internal stress generated during KOVAR  machining also prepares the material structure for the implementation of the subsequent process-the sealing process of the metal parts.

The main purpose of annealing Kovar shell before sealing is to:

(1) Eliminate machining stress.

When Kovar undergoes plastic machining deformation during cold working, about 10% to 15% of the applied energy is converted into internal energy, which is commonly referred to as internal stress, so that the Kovar material structure is in an unstable state. Under this condition, it can be maintained for a long time without significant changes. Once it is heated, a series of changes in structure and properties will occur, and the material structure tends to a stable state. This change in structure and properties, especially changes in the structure of the structure, is reflected on the sealing surface The tensile stress on the molybdenum group glass during high temperature sealing may cause the glass to produce small cracks and leak;

(2) Eliminate work hardening.

In the process of cold working, cnc manufacturing and forming of Kovar parts, due to defects such as grain elongation and grain breakage in the internal material structure, crystal defects and dislocation density increase greatly. The smaller the distance between the dislocation and the dislocation, the greater the interference between each other, and the greater the distortion of the surrounding lattice. Each dislocation line has a stress field, and the dislocation and dislocation pass through each The interaction of the stress field causes the hardness and elasticity of Kovar to increase, while the plasticity decreases, which is work hardening. If the work hardening is not eliminated, the stress field of the interaction between dislocations and dislocations will be broken due to crystal recovery or recrystallization during high-temperature sealing, and the balance will be lost. This also affects the sealing of metal and glass. Certain stress effects;




Alan Lan

Foreign trade manager

General Manager's Office | Wonder Group

13712198704 | 15112807161
info@wonders-group.com
https://beryllium-copper.com/
No 3,Zhengda Road,Shatou Village,Chang'an Town,Dongguan City,Guangdong Province,China


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What material is used for medical parts

According to the working characteristics of medical parts, it is required to be resistant to a certain temperature during disinfection (usually high-temperature steam disinfection), not to be rusty, high in strength, hardness (scalpel), and not easy to deform. Generally, stainless steel is selected, and stainless steel has The materials with the above characteristics are martensitic stainless steel, such as 3Cr13 and 4Cr13 martensitic stainless steel and 9Cr18 machining stainless steel spring , etc., and martensitic stainless steel is the cheapest stainless steel, which can meet the requirements of medical equipment.
The heat treatment process is basically quenching + low temperature tempering.

  • 3Cr13 steel quenching temperature 1000~1050°, oil quenching, tempering temperature 150~350°
  • 4Cr13 steel quenching temperature 1050~1100°, oil quenching, tempering temperature 150~350°

When tempering these two kinds of steel, try to choose a higher temperature, such as 300 °, for the need of high temperature disinfection (high temperature disinfection water vapor can reach 300 °)

The quenching temperature of 9Cr18 steel is 1000~1050, oil quenching, tempering temperature is 200~300. Of course, the above mentioned are all kinds of surgical medical machining equipment, injection puncture equipment, plastic surgery equipment, general examination equipment, family planning equipment, orthopedics (Orthopedics) ) Surgical instruments and other materials, such as scalpels (scalpel handles and blades, skin knives, wart peeling knives, lancets, spatulas, razors, dander scrapers, picking knives, front knives, pedicure knives , Manicure knife, scalpel), surgical scissors (ordinary surgical scissors, tissue scissors, comprehensive tissue scissors, suture removal scissors, plaster scissors, dissecting scissors, gauze bandage scissors, educational surgical scissors), various forceps (ordinary hemostatic forceps) , Small blood vessel hemostatic forceps, mosquito hemostatic forceps, tissue forceps, cemented carbide insert needle holders, ordinary needle holders, wound crimping forceps, skin pressure forceps, bullet forceps, gauze peeling forceps, sponge forceps, scarf forceps , Skin tube forceps, instrument forceps), forceps for basic surgery (small vessel forceps, non-invasive forceps, tissue forceps, plastic forceps, needle-holding forceps, health forceps (simple forceps), plucking forceps, tissue forceps, dressing forceps , Dissecting forceps, hemostatic clip), basic surgical needles, hooks (aneurysm needles, probes, hair pushing needles, hair transplanting needles, picking needles, straight-pointed needles for teaching, vein retractors, wound hooks, flat retractors, double-ended retractors , Skin retractors, anatomical hooks), stethoscopes, etc., do not include the machining materials of medical equipment, such as X-ray machines, B-ultrasound, CT, photographic equipment, laboratory equipment, etc. The materials of these overall equipment are based on the technical requirements of the parts of the equipment Different, you can choose from a wide range of varieties.




Alan Lan

Foreign trade manager

General Manager's Office | Wonder Group

13712198704 | 15112807161
info@wonders-group.com
https://beryllium-copper.com/
No 3,Zhengda Road,Shatou Village,Chang'an Town,Dongguan City,Guangdong Province,China


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Analysis of Difficulties in Processing of Medical Parts and Devices

90% of medical machining parts and equipment implants are made of Ti6Al-4V titanium alloy, which is derived from light weight, high strength and high biocompatibility. Titanium alloy 6AL-4V has become a commonly used material for medical implant equipment. Titanium alloy 6AL-4V is usually used in the production of hip joints, bone screws, knee joints, bone plates, dental implants, and spine connection components. Titanium alloy has the characteristics of work hardening, the cutting angle is large in the processing process, and the chips produced are thin. A relatively small contact area is formed on the surface.

1. Titanium alloy materials that are difficult to process for medical parts

The high speed laser cutting force during the machining process, combined with the frictional force during chip flow, will comprehensively lead to excessive local cutting heat of the tool. The poor thermal conductivity of titanium alloys prevents the cutting heat from being conducted quickly. As a result, a large amount of cutting heat is concentrated on the cutting edge and the tool surface. High cutting force and cutting heat will comprehensively cause crescent craters and cause rapid tool failure.

The relatively low modulus of elasticity makes titanium alloys more elastic than steel. Therefore, excessive cutting force should be avoided to ensure that the rebound of the workpiece is small. Thin-walled parts have a tendency to deform under tool pressure, causing chatter, friction and even tolerance problems. The key to solving the problem is to ensure the rigidity of the entire system. It is very necessary to use tools with sharp cutting edges and correct geometric shapes. In addition, machining titanium alloys have a tendency to chemically react and alloy with cutting tools at high temperatures, and their chips have a tendency to be welded to the surface of the tool.

2. Reliable and compact machine tool fixture

Medical equipment processing equipment needs to be able to process small and complex parts made of difficult-to-process materials (such as titanium alloy or stainless steel) with high accuracy requirements. For example, processing bone and joint replacement parts is quite complicated. Due to the poor cutting performance of the material being processed, the blank is usually a bar stock-which means that a large amount of metal needs to be removed. As a result, some parts are cast into a shape close to the finished product, but this also adds to the trouble-the need to manufacture complex and expensive fixtures. Another factor that increases processing complexity is the narrow tolerance range.

Medical equipment parts and components have high requirements for material, processing accuracy, and surface finish, which requires high reliability of the processing system. Therefore, extremely high requirements are placed on machine tools, fixtures, cutting tools, and CAM software. Workpieces are usually processed on advanced medical equipment processing equipment such as Swiss automatic lathes, multi-spindle machine tools and rotary tables. These machine tools are mostly characterized by very small size and very compact structure.

The characteristics and requirements of medical device parts processing have undoubtedly promoted the development of processing technology and solutions to improve the competitiveness and production efficiency of small and medium-sized enterprises in machining medical devices.




Alan Lan

Foreign trade manager

General Manager's Office | Wonder Group

13712198704 | 15112807161
info@wonders-group.com
https://beryllium-copper.com/
No 3,Zhengda Road,Shatou Village,Chang'an Town,Dongguan City,Guangdong Province,China


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KOVAR parts seal preparation and physical properties

Kovar® is a vacuum-melted iron-nickel-cobalt low-expansion alloy. The chemical composition content is controlled in a very narrow range to ensure accurate and balanced thermal expansion performance. At the same time, strict quality control during the manufacturing process of KOVAR machining parts also ensures balance Its physical and mechanical properties are more suitable for deep drawing, stamping and various cutting processes.

Material use

Kovar® is used for vacuum sealing of hard glass and ceramics, and is widely used in electron tubes, microwave tubes, transistors and diodes. On integrated circuits, it is used for flat integrated circuits and dual in-line packages.

Seal preparation

All parts made by Kovar® should be degassed and annealed in a wet hydrogen atmosphere. Hydrogen is injected into water at room temperature and gets wet through blisters. Care must be taken to prevent surface carbonization. The heat treatment furnace must have a cooling chamber that provides the same atmosphere. The heat treatment is carried out in the temperature range of 1540/2010°F (838/1099°C). The heat treatment time starts from a low temperature and rises to a high temperature in 20 minutes. Then the parts are moved to the cooling zone and cooled to 570°F (299° C) Then take it out.

When sealing between metal and hard glass, it is recommended that the metal has an oxide film. The preferred oxide film is thin and tightly adsorbed on the metal surface treatment. Such an oxide film can be heated to 1200/1290°F (650/700°C) in an atmospheric environment and continue for a period of time until the dark gray surface layer turns into a light brown oxide film.

  • Physical properties
  • The proportion is 8.36;
  • Density 0.3020lb/in3;
  • Thermal conductivity 120.0 BTU-in/hr/ft²/°F;
  • Elasticity coefficient (E) 20.0 x 103 ksi;
  • Resistance (70.0°F) 294.0 ohm-cir-mil/ft;
  • Curie temperature 815°F;
  • The melting point is 2640°F.
  • magnetic

Kovar alloy machining are magnetic below the Curie temperature, and the magnetic properties depend on heat treatment. The smaller the hardness, the higher the permeability and the smaller the hysteresis loss.




Alan Lan

Foreign trade manager

General Manager's Office | Wonder Group

13712198704 | 15112807161
info@wonders-group.com
https://beryllium-copper.com/
No 3,Zhengda Road,Shatou Village,Chang'an Town,Dongguan City,Guangdong Province,China


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Do you know how to test the processing density of metal parts?

Metal parts processing density tester KW-300A, metal parts, refers to the collective name of various specifications and shapes of metal blocks, metal rods, metal tubes, etc. made of metal materials. In the production process, density is very important. One of the physical properties is that manufacturers need to strictly control the density of products.

KW-300A is a precision instrument composed of electronic machining balance, density software, density accessories, etc. It can quickly and conveniently measure the density of solids of various shapes, equipped with professional measuring accessories and transparent sinks. It is easy to carry, simple to operate, powerful, high precision and repeatable.

  • KW-300A parameters and features:
  • Weighing range: 0.005g~ 300g
  • Density/specific gravity accuracy: 0.001 g/cm3
  • Test time is about 5 seconds;
  • Display value density, volume temperature compensation;
  • Solution temperature can be set to 0~100℃/auto;
  • Compensation solution The compensation solution can be set to 19.999.

Directly read the density and volume of solid blocks, particles, and floating bodies of any shape with a density of >1 or <1, ​​with temperature compensation setting and solution compensation setting functions, more user-friendly operation, and more in line with the needs of field operations. The density measuring table is integrated by injection molding, which is convenient and quick to install and has a longer use time.

The one-piece anti-corrosion large sink design is adopted to reduce the error caused by the buoyancy of the hanging railing line, and it is also convenient to test larger bulk objects.

With the function of upper and lower density limits, it can judge whether the specific gravity of the test object is qualified or not. Equipped with buzzer device.

Built-in battery, equipped with windshield, more suitable for on-site testing. Applicable to: rubber, wire and cable, aluminum products, plastic particles, powder metallurgy, mineral rock, precision ceramics, glass industry, metal products, precision ceramics, refractory materials, magnetic materials, alloy materials, mechanical parts, metal recycling, minerals and Research laboratories for new materials such as rock, cement manufacturing, and jewelry industries.



Alan Lan

Foreign trade manager

General Manager's Office | Wonder Group

13712198704 | 15112807161
info@wonders-group.com
https://beryllium-copper.com/
No 3,Zhengda Road,Shatou Village,Chang'an Town,Dongguan City,Guangdong Province,China


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Precautions for machining aluminum parts on CNC lathes

​CNC lathe parts are processed with a variety of raw materials. Among them, aluminum parts are one of the more processed parts. When using CNC machine tools to process aluminum machining parts, you want to make the processing models and specifications more stable. Such areas must It is necessary to pay attention to the refrigeration problems of raw materials and the deformation of aluminum die castings after refrigeration. Such things are generally inevitable. At this time, it is necessary to pay attention to the application of diesel engine refrigerant as much as possible. Consider the deformation of raw materials.

Processing technology

Unscientific processing technology can easily lead to deviations in the model specifications of aluminum die castings. To ensure the basic processing technology (such as cutting CNC machine tool processing "first rough and then fine, face first and then hole, first many and then spicy small surface" or welding fixture application "reduce the frequency of clamping and use as much as possible to form fixtures" It is necessary to avoid the machining deviation caused by iron pins on aluminum parts as much as possible.

Basic parameters

Cutting rates, cutting speeds, cutting factors, and tool compensation are all cutting factors that impair the efficiency of processing, so special attention should be paid. Tool selection

When machining aluminum parts, use special-purpose tools as much as possible. Such tools are generally more purposeful. For example, turning tools special for aluminum milling generally have larger rake angles and helix angles, sharper cutting edges, which are more conducive to the processing of aluminum parts (such as anti-chip buildup), and the processed performance indicators will be stronger.

Stress field level

The aluminum material is too soft, so try to pay extra attention to the clamping range. In addition, during processing, the aluminum parts are roughed intact and left for a period of time before the next production process is carried out to remove the stress field.

In addition, it is necessary to pay attention to the milling surface and the demand of cutting fluid during the processing of aluminum parts. There are many factors that impair the efficiency of aluminum processing, so it should be handled flexibly during processing, and the actual problems should be analyzed in depth. Stable machine tools, effective processing techniques and tools, and the technical strength of their operators are all factors that impair product quality.

Tool selection

When machining aluminum parts, try to use special tools, which are generally more targeted. For example, lathes for aluminum milling generally have larger rake angles and helix angles, and the laser cutting edges are sharper, which is more conducive to the processing of aluminum parts (such as anti-chip buildup), and the processing performance will be stronger.

In addition, special attention should be paid to the difficulty of milling and the amount of cutting fluid required in the processing of aluminum parts. There are many factors that damage the credibility of aluminum processing, so it should be handled flexibly during processing, and specific difficulties should be analyzed in detail. Stable machine tools, reasonable processing technology and cutting tools, and the technical level of operators are all factors that harm product quality.

Processing technology

Unreasonable processing technology can easily cause errors in specifications and models of cast iron parts. In ensuring the basic processing technology (such as cutting CNC machine tools

Most of the basic processing technology key links such as "coarse first and then fine, surface first, hole first, many spicy noodles first" or "reduce the number of clamping times, try to use the composition of the tooling and fixture" in the use of fixture tools) Reduce machining errors caused by iron pins on aluminum parts.
There are many reasons for the deformation of aluminum parts, which are often related to raw machining materials, parts appearance, and production and processing specifications. There are several important aspects: deformation caused by blank welding stress, deformation caused by cutting force and cutting heat, and deformation caused by clamping force.




Alan Lan

Foreign trade manager

General Manager's Office | Wonder Group

13712198704 | 15112807161
info@wonders-group.com
https://beryllium-copper.com/
No 3,Zhengda Road,Shatou Village,Chang'an Town,Dongguan City,Guangdong Province,China


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The production process of KOVAR parts processing has a great relationship with the process, including the process environment elements and the optimization configuration elements of the process route. The process route process needs to be formulated by an experienced person. The following is a brief explanation of the process process.

The formulation of the process route process: First, the geometric structure of the parts, the core parts of the accuracy index, the accuracy requirements, material characteristics, heat treatment requirements and performance requirements, etc. should be carefully analyzed, and then the blanks of the parts should be reasonably selected, the cnc machining china equipment should be used reasonably, and reasonable measures should be taken. Many process links such as stress process measures are reasonably configured. In the production organization process, the process is strictly implemented. During the process, strict inspection is performed. For general precision parts, the process route is: rough machining-aging-semi-finishing -Finishing can be done. Facing the processing of precision mechanical parts, such a processing route is obviously not enough. The processing route must be lengthened, and aging treatment must be properly interspersed, and super-finishing procedures are configured to ensure the processing requirements.

The usual process flow is: primary roughing-primary thermal aging-secondary roughing-secondary thermal aging (or vibration aging)-semi-finishing-vibration aging is enough-finishing-natural aging (or low temperature stability treatment)-precision Processing. Among them, the heat treatment requirements of precision parts should be arranged according to the different requirements of the overall hardness, partial hardness, and surface hardness of the parts. The stable processing of the precision mechanical parts processing accuracy is also very critical and complex, simple one or two. This method has been unable to meet the requirements, and usually adopts a variety of methods according to needs, such as stress annealing, low temperature stabilization, vibration aging, natural aging, and even cold treatment to achieve the accuracy and stability requirements of precision parts.

In order to ensure the machining accuracy, roughing and finishing are best performed separately. Because of the large amount of cutting during rough metal machining, the workpiece is subjected to large cutting force, clamping force, heat generation, and the machined surface has a significant work hardening phenomenon, there is a large internal stress inside the workpiece, if rough or rough machining Continuously, the precision of the parts after finishing will be quickly lost due to the redistribution of stress. For some parts that require high machining accuracy. After rough machining and before finishing, low temperature annealing or aging treatment procedures should also be arranged to eliminate internal stress.




Alan Lan

Foreign trade manager

General Manager's Office | Wonder Group

13712198704 | 15112807161
info@wonders-group.com
https://beryllium-copper.com/
No 3,Zhengda Road,Shatou Village,Chang'an Town,Dongguan City,Guangdong Province,China


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The technological process of precision parts processing!

In the actual application of precision parts processing, the higher the precision and the more refined the better the processing level and quality. At the same time, these products are also more popular with consumers. Generally speaking, they have incomparable advantages and characteristics in CNC machining. Precision parts processing will choose processing methods according to customer requirements, or make decisions based on products, and the same is true for precision parts processing.



The machining process of precision parts includes cnc turning, milling, planing, grinding, clamp, stamping, casting, etc.

Stamping: Stamping uses pre-made molds and punches for cold stamping, mainly for sheet metal processing, that is, most of the processed materials are plates, and the processing efficiency is relatively high and suitable for mass production

The precision hardware processing process is divided into engineering molds and continuous molds. Engineering plastic molds are also called single-punch dies. Some more complex parts require several sets of molds, and the continuous mold is divided into several parts in the cavity of the mold. In a mold, one stroke processed by such a punch is a finished product. High-speed continuous punching machine can process three to four hundred products per minute

Lathes: Lathes for precision parts processing belong to precision machining machinery. They are divided into ordinary lathes, automatic lathes, instrument lathes and computer lathes. They rotate and move after clamping the material, and the lathe performs radial or axial processing.

Nowadays, automatic lathes and computerized lathes are more and more widely used, because these two are fully automatic processing, which reduces the accuracy error caused by human operation to the lowest point, and the processing speed is fast, which is used for mass production. Most of the lathes are equipped with side rotary tools and back rotary tools. In other words, milling can also be performed on a lathe.

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Common sense of CNC lathe processing

Repetitive production of parts processed by CNC lathes: the use of CNC grinders accounts for a relatively high proportion of process preparation man-hours, such as process analysis preparation, programming, part adjustment and test cutting, etc. The sum of these comprehensive man-hours is often a single part The processing time is dozens to hundreds of times, but the work content of these CNC turning can be saved and used repeatedly. Therefore, when a part is successfully trial-produced on the CNC grinder and then repeatedly put into production, the production cycle is greatly reduced, the cost is less, and more can be obtained. Good economic benefits.



It is required to focus on ensuring the quality of the key parts in small and medium batches that can be produced efficiently: CNC grinding machines can achieve high-precision, high-quality, and high-efficiency grinding machining under computer control. Compared with the special grinding machine, it can save a lot of special process equipment, has a strong flexible manufacturing capacity and obtains better economic benefits. Compared with ordinary grinders, it can eliminate many man-made interference factors in the long process flow of complex machining, and the accuracy of machining parts is good, the interchangeability is good, and the machining efficiency is high.

The parts processed by the CNC lathe should meet the technological characteristics of the multi-process centralized processing of the CNC grinder or 3d printing. When the CNC grinder processes the parts, the grinding wheel cuts the workpiece and the corresponding non-nc grinder is exactly the same, but it can perform some processing accuracy requirements For example, in terms of grinding range, ordinary grinders are mainly used to grind cylindrical surfaces, circular CNC lathe cones or the end faces of stepped shoulders. In addition, CNC cylindrical grinders can also grind circles. Torus, as well as the above complex combined surfaces in various forms.

   The processing batch of parts should be larger than that of ordinary lathes and batches of CNC lathes. When processing small and medium batches of parts on non-CNC grinders, due to various reasons, the pure cutting time only accounts for 10%-30% of the actual working hours. When china cnc turning on a multi-process centralized CNC grinding machine such as a grinding machining center, this ratio may rise to 70% to 80%, but the preparation time for adjustment is often much longer, so the part batch will become too small. Uneconomical.

Considerations for the processing of some special cnc machining parts processed by CNC lathes. Although some parts are processed in small batches, ordinary lathes have complex shapes, high quality and good interchangeability. This cannot meet the above requirements on non-CNC grinders and can only be arranged. Processing on CNC grinders, such as parabola, cycloid cams and special-shaped mirrors.

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What details should be paid attention to in the processing of CNC lathe parts ​

In fact, what a workpiece can see is not only the strength of a manufacturer, but also its handling of some details.

For CNC lathe parts, if the cnc manufacturer does not handle it well, then this machining part is not acceptable.



What should the manufacturer pay attention to when cnc machining?

  • 1. The burr on the cost surface can be said to be easily overlooked by many manufacturers. Many people say what this part looks like when it comes out, and what it looks like when the finished product is packaged. In fact, for a part, the CNC lathe 5 axis cnc machining parts are completed by equipment, then the cloak will be produced during injection molding, and this burr is also produced at this time. If it is not trimmed in time, or the The parts are obsolete. Otherwise, it will affect other links during use.
  • 2. Accuracy of parts. For CNC lathe machining parts, its accuracy is very strict. It can only be used if it meets the required accuracy. The accuracy of the part is judged mainly by its control of the size. Ability, if it is within the tolerance that can fluctuate, then the part is qualified, if it is out of tolerance, then it is unqualified.
  • 3. Analysis of the test results. For china mfg component, it will inevitably undergo a performance test before it leaves the factory. If the performance is qualified, it will be shipped out. If it is not qualified, then it should be analyzed. In this way, it can also avoid mass scrapping. Manufacturers in the machining industry will basically deal with it in this way. They will make certain quality control charts based on the performance of many companies to analyze the reasons.
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Six points of experience in precision metal parts processing

In the precision  machining of metal parts, hardware processing accounts for a large part. This time I will share with you what are the technological properties of hardware, I hope it will be helpful to everyone!

Casting performance: refers to some process properties of whether a metal or alloy is suitable for casting, including flow properties, ability to fill the mold; shrinkage, the ability to shrink the volume when the investment casting solidifies; segregation refers to the unevenness of chemical composition.

Welding performance: refers to the characteristics of metal materials that can meet the purpose of use by welding two or more metal materials together by heating or heating and pressure welding.



Top gas section performance: refers to the performance that laser cutting materials can bear upsetting without breaking.

Cold bending performance: refers to the performance of metal materials that can withstand bending without breaking at room temperature. The degree of bending is generally expressed by the ratio of the bending angle α (external angle) or the bending center diameter d to the material thickness a. The larger a or the smaller d/a, the better the cold bendability of the material.

Stamping performance: the ability of metal materials to withstand stamping deformation without breaking. Stamping at room temperature is called cold stamping. The inspection method is tested by cupping test.

Forging performance: the ability of metal materials to withstand plastic mold deformation without breaking during forging.

Processing is divided into the following four stages:

1.Face before hole

For parts such as box body, bracket and connecting rod, the plane should be processed first and then the hole should be processed. In this way, the holes can be positioned on the plane to ensure the accuracy of the plane and the position of the hole, and the processing of the holes on the plane is convenient.

2. Process the datum surface first

During the processing of the part, the surface as the positioning reference should be processed first in order to provide a precise reference for the subsequent processing as soon as possible. Called "benchmark first."

3. Finishing

The finishing cnc machining  china of the main surface (such as grinding, honing, fine grinding/rolling processing, etc.) should be carried out at the latter stage of the process route. The surface finish after processing is above Ra0.9um. A slight collision will damage the surface. In Japan , Germany and other countries, after the finishing process, they must be protected with flannel. Never touch the workpiece directly with your hands or other objects, so as to avoid the finishing surface from being damaged due to the transfer and installation between processes.

4, divide the processing stage

Surfaces with high processing quality requirements are divided into processing stages, which can generally be divided into three stages: rough processing, semi-finishing and finishing. The main purpose is to ensure the processing quality; facilitate the rational use of equipment; facilitate the arrangement of the heat treatment process; and facilitate the discovery of blank defects.

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KOVAR parts cold working manufacturing process

KOVAR parts are precision processed by CNC numerical control machine tools and used for electronic industry equipment; precision parts processing, swiss machining, CNC precision parts processing.



(1) Eliminate machining stress.

When Kovar undergoes plastic deformation during cold working, about 10% to 15% of the applied energy is converted into internal energy, which is commonly referred to as internal stress, so that the Kovar machining material structure is in an unstable state. Under this condition, it can be maintained for a long time without significant changes.

Once it is heated, a series of changes in structure and properties will occur, and the material structure tends to a stable state. This change in structure and properties, especially changes in the structure of the structure, is reflected on the sealing surface.

The tensile stress on the molybdenum group glass during high temperature sealing may cause the glass to produce small cracks and leak air.

(2) Eliminate work hardening.

In the process of cold working, cnc manufacturing and forming of Kovar parts, due to defects such as grain elongation and grain breakage in the internal material structure, crystal defects and dislocation density increase greatly. The smaller the distance between the dislocation and the dislocation, the greater the interference between each other, and the greater the distortion of the surrounding lattice.

Each dislocation line has a stress field, and the dislocation and dislocation pass through each The interaction of the stress field causes the hardness and elasticity of Kovar to increase, while the plasticity decreases, which is work hardening.

If the work hardening is not eliminated, the stress field of the interaction between dislocations and dislocations will be broken due to crystal recovery or recrystallization during high-temperature sealing, and the balance will be lost. This also affects the sealing of alloy machining and glass. Certain stress effects.

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What are the reasons for the failure of metal parts?

The basic forms of failure of metal parts. Generally, the failure forms of mechanical parts are classified according to the external morphological characteristics of the failed parts, which generally include: wear failure, fracture failure, corrosion failure and distortion failure. In production practice, the most important failure mode is The wear failure of the working surface of the part, and the most dangerous form of failure is the instantaneous crack and fracture, collectively referred to as fracture failure.

​Basic forms of failure of metal cnc machining parts Generally, the failure modes of mechanical parts are classified according to the external morphological characteristics of the failed parts, which generally include: wear failure, fracture failure, corrosion failure and distortion failure. In production practice, the most important failure mode It is the wear failure of the working surface of the part, and the most dangerous form of failure is instantaneous cracks and fractures, collectively referred to as fracture failure.


1. Wear failure of parts

Friction and wear are a common phenomenon in nature. When parts or parts and other substances come into contact with each other and produce relative motion, it is called friction. The phenomenon of material loss on the friction surface of the part is called the wear of the china cnc machining part. Material wear includes two aspects: one is the damage of the material structure; the other is the change of size, shape and surface quality (roughness). If the wear of the parts exceeds a certain limit, it will lose its specified functions, causing the equipment to decline or fail to work. This situation is called wear failure. According to tribological theory, edm machining parts wear can be divided into abrasive wear, adhesive wear, fretting wear, erosion wear and corrosion wear according to their properties.

  • ① Abrasive wear: The phenomenon that the surface of parts and abrasives rub against each other, which causes the loss of surface material is called abrasive wear or abrasive wear. Abrasives also include hard asperities on the surface of the part. Among wear failures, abrasive wear failure is the most common and most harmful one.
  • ② Adhesive wear: Adhesive wear refers to the wear caused by two relatively sliding surfaces that are welded together locally, so that the material on one surface is transferred to the other surface.
  • ③Fatigue wear: When the two contact surfaces of the friction pair are relatively rolling or sliding, the periodic load will subject the contact area to a large alternating contact stress, causing fatigue cracks on the metal surface and continuous expansion, causing the surface material to fall off, causing points Corrosion and peeling, this phenomenon is called surface fatigue wear.
  • ④ Fretting wear: Fretting wear is the surface damage caused by relatively small vibration on two fixed contact surfaces, which mainly occurs on the joint surface of relatively static parts. The main hazard is to reduce the accuracy of the fit and loosen the tightly-fitted body. What is more serious is to cause stress concentration and cause fatigue fracture of the parts.
  • ⑤ Erosion wear: Erosion wear refers to the loss of the surface when the material is impacted by fixed particles, droplets or liquid bubbles.

2. Fracture failure of parts

The phenomenon of mechanical cnc manufacturing parts split into two or more pieces under the action of certain factors is called fracture. The new surface formed after the fracture of the part is called fracture.

  • ① Overload fracture: When the applied load exceeds the ultimate stress that its dangerous section can bear, the part will fracture. This kind of fracture is called overload fracture. Unreasonable strength design of parts, excessive stress on the structure, operation errors, overloaded operation of mechanical equipment, and excessive load on certain parts may lead to overload fracture.
  • ②Fatigue fracture: The fracture phenomenon of metal parts after a certain number of cyclic loads or alternating stresses is called fatigue fracture, also known as mechanical fatigue.
  • ③Brittle fracture: due to improper manufacturing process of metal parts, or corrosion by harmful media during use, or uncomfortable ambient temperature, the material may become brittle and the metal parts may suddenly fracture. Fractures of this nature are generally called brittle fractures, but also called environmental fractures.
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PTJ Hardware cnc machining factory
Sifangyuan Industrial Park, Xinshapu, Huaide Community
Humen town, Dongguan City, Guangdong Province
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