Metal Injection Molding
Application Of Metal Injection Molding MIM in The Field Of Hardware Tools
Qinhuangdao Zhongwei Precision Machinery Co., Ltd. is a company specializing in the development and sales of powder metallurgy products. The company has professional laboratories, MIM/PM factories and mold development centers. The main products are MIM development, MIM products, PM development, PM products, etc., the products are widely used in the automotive industry, machinery industry, household appliances, communication products, electric hand tools, hardware tools, micro-motors, medical machinery, toy accessories, lock parts and so on.
Metal injection molding (MIM) complex structural parts, powder press forming (PM) precision hardware, gears, sprockets, gearboxes, oil-impregnated bearings, bushings, locks, mobile phone accessories, home appliance accessories, complex special-shaped structural parts.
Metal powder injection molding (MIM) technology is a low-cost, high-efficiency process that can customize the processing of complex and smaller metal hardware accessories. For one such process, it is also known as: popular parts molding technology. So what are the advantages of metal powder injection molding (MIM) technology in application?
Application advantages of MIM injection molding technology:
1. It can minimize the segregation of alloy components and avoid the uneven state of the as-cast structure.
2. It can be used in a series of high-performance non-equilibrium materials such as amorphous and microcrystalline, crystal preparation, nanocrystalline, and supersaturated solid solution. These materials have excellent electrical, magnetic, optical and mechanical properties.
3. Metal powder injection molding (MIM) technology can perform near-net-shape and automated mass production, reducing the consumption of production resources and energy.
4. It can produce MIM materials and products with special structure and properties that can be produced by ordinary smelting methods, such as new porous materials, porous separation membrane materials, MIM communication medical materials, high-performance structural ceramic abrasives and MIM ceramic case materials.
5. It can make full use of the scale of ore, tailings, steelmaking sludge, and rolling mills, and recycle metal waste as raw materials. As a new technology, metal powder injection molding (MIM) can be used for material recovery and comprehensive utilization. In line with the current concept of green environmental protection.
1. MIM concept and process flow
MIM is the abbreviation of Metal Injection Molding.
Metal powder injection molding is a high-tech combination of traditional powder metallurgy technology and plastic injection molding technology. It is a revolution in the forming process of small and complex parts. It uniformly mixes the applicable technical powder and binder into a rheological feed, which is injection-molded on an injection machine. The obtained blank is degreased and then sintered and densified into a finished product. If necessary, post-processing can also be performed.
The production process is as follows
Batching→kneading→granulation→injection molding→chemical extraction→high temperature debonding→sintering→post-processing→finished product
2. MIM technical features
Metal powder injection molding combines the advantages of powder metallurgy and plastic injection molding technology, breaking through the limitations of traditional metal powder molding technology in product shape, and using plastic injection molding technology to produce large-scale and high-efficiency plastic injection molding with complex shapes. Parts: such as various external grooves, external threads, tapered external surfaces, cross-holes, blind holes, recesses, key pins, rib plates, surface knurling, etc.
• Advantages of MIM technology
a. Directly form parts with complex geometric shapes, usually weighing 0.1~200g
b. Good surface finish and high precision, typical tolerance is ±0.05mm
c. Good flexibility of alloying, wide application range of materials, product density of 95%~99%, uniform internal structure, no internal stress and segregation
d. High degree of production automation, no pollution, can achieve continuous large-scale clean production
• Comparison of MIM and precision casting forming ability
Features | Precision casting | Mim |
Minimum hole diameter | 2mm | 0.4mm |
2mm diameter blind hole maximum depth | 2mm | 20mm |
Minimum wall thickness | 2mm | <1mm |
Maximum wall thickness | Unlimited | 10mm |
4mm diameter tolerance | ±0.2mm | ±0.05mm |
Surface roughness (Ra) | 5μm | 1μm |
• Comparison of MIM and other forming processes
Project | MIM | Powder Metallurgy | Precision casting | Machining |
Density | 98% | 86% | 98% | 100% |
Tensile Strength | High | Low | High＞ | High |
Finish | High | Middle | Middle | High |
Miniaturization ability | High | Middle | Low | Middle |
Thin wall capability | High | Middle | Middle | Low |
Complexity | High | Low | Middle | High |
Design Tolerance | High | Middle | Middle | Middle |
Material range | High | High | Middle | High |
3. MIM commonly used materials
Material System | Synthetic Ingredients |
Low-alloy steel | fe-2ni, f-8ni |
Stainless steel | 316l、430l、17-4ph |
Tool steel | 42cr2mo4、m2 |
Carbide | wc-co(6%) |
Heavy alloy | w-ni-fe、w-ni-cu、w-cu |
4. Basic properties of several MIM materials
Material | Density (103kg/cm3) | Hardness | Tensile strength mpa | Elongation | |
Iron-based alloys | pim4600 | 7.68 | 85hrb | 400 | 25 |
pim4650 | 7.68 | 100hrb | 600 | 15 | |
Stainless steel | 316l | 7.94 | 52hrb | 580 | 45 |
Tungsten Alloy | 95%w | 18.1 | 31hrc | 930 | 10 |
5. Typical application fields of MIM products
Aerospace industry: wing hinges, rocket nozzles, missile tails, turbine blade cores, etc.
Automotive industry: airbag components, ignition control lock components, turbocharger rotors, seat components, brake components, etc.
Electronics industry: disk drive components, cable connectors, electronic packages, cell phone vibrators, computer print heads, etc.
Military industry: mine rotors, gun triggers, armor-piercing bullets, quasi-constellations, cluster bullets, etc.
Daily necessities: watch cases, watch straps, buckles, golf heads and tees, sewing machine parts, electric toy parts, etc.
Machinery industry: special-shaped milling cutters, cutting tools, power tool parts, micro gears, hinges, etc.
Medical equipment: orthodontic frame, scissors, forceps, scalpel, etc.
6. Suitable material
Stainless steel fe alloy fe-ni-co alloy Tungsten titanium alloy Tool steel High speed steel Cemented carbide Alumina Zirconia
Metal powder injection molding (MIM) technology has unique chemical composition as well as mechanical and physical properties. Therefore, the application of metal powder injection molding technology will become more and more extensive.