Stainless Steel Powder Metallurgy Sintered Parts

Stainless steel powder metallurgy sintered parts Powder metallurgy products using pre-alloyed stainless steel powder as raw materials. Such as stainless steel filters, fire arresters, etc.

Applied disciplines: material science and technology (first-level discipline), metal materials (second-level discipline), powder metallurgy materials (third-level discipline).

Qinhuangdao Zhongwei Precision Machinery Co., Ltd. Powder Metallurgy Division was established in 2007 and is located in Qinhuangdao City, Hebei Province. There are two production lines for metal injection molding MIM process and powder metallurgy PM. The company's existing self-developed products: German Maya warp knitting machine Sensing chain blocks, electric actuator gears, automobile oil pump rotors, washing machine transmission gears and other products, the powder metallurgy products produced cover automobiles, motorcycles, power tools, home appliances, textile machinery parts and other fields. Our company is a comprehensive high-tech enterprise integrating R&D, production and sales of copper alloy, iron base, stainless steel base, aluminum alloy, nickel alloy, cobalt alloy, tungsten alloy, cemented carbide and powder metallurgy structural parts.

Zhongwei Precision's long-term technical research and reserves can now convert a considerable part of the parts into powder metallurgy products through the use conditions and stress conditions of steel parts and casting products provided by customers, so as to reduce procurement costs and production costs for customers. the goal of. We have successfully converted the German Maya warp knitting machine sensor chain block, electric actuator double gear, large circular knitting triangle and other steel or casting products into powder metallurgy products, saving customers from 15% to 80%. Procurement cost, and widely recognized by customers.

Product Description

1. Implementation standards: the company strictly implements ISO9001, ISO14001, IATF16949 certification

The products have passed the certification of ROHS, FDA EU, etc.

2. Product material standards: ISO, GB, ASTM, SAE, EN, DIN, BS, AMS, JIS, ASME, DMS, TOCT, GB

3. Main processes: metal injection molding MIM, powder metallurgy PM, investment casting, die-casting aluminum,

4. Available materials for powder metallurgy:

Copper alloy, iron base, titanium alloy, stainless steel base, aluminum alloy, nickel alloy, cobalt alloy, tungsten alloy, cemented carbide, hydroxy alloy, soft magnetic material and 3D printing can be customized according to customer requirements.

How to improve product density?

In the development of Stainless steel powder metallurgy sintered parts, it is imperative to increase the density of stainless steel.

1. Super solidus sintering:

(1) Traditional stainless steel sintering generally adopts solid-phase sintering, but solid-phase sintering will generate a large number of residual pores in stainless steel. Supersolidus liquid phase sintering allows the stainless steel pre-alloyed powder to form a liquid phase during the sintering process. The liquid phase fills the pores by flow to increase the density and properties of the sintered body.

(2) The density, hardness, wear resistance and corrosion resistance of 1400 ℃ super solidus liquid phase sintered stainless steel are all higher than 1200 ℃ solid phase sintering. Care should be taken to avoid excessive grain growth and excessive sintering due to excessive sintering temperature. combustion.

2. Use appropriate additives:

(1) Some low melting point alloy elements are added to the powder to reduce the porosity through the liquid phase formed during the sintering process, so that the stainless steel can meet higher performance requirements. For example, 2%-8% copper-based alloy is added to the commonly used 304 stainless steel. Due to the low melting point of copper, the liquid phase can be formed at 960 °C, and the entire liquid phase can be formed at 1000 °C. When the temperature is higher than the melting point of copper, the liquid phase flow makes the surface pores continue to terraform and shrink. Due to the wetting of copper It has good properties and can be evenly distributed. On the stainless steel substrate, a sintered body is produced. As the pores decrease, the microhardness also increases.

(2) In order to improve the performance of stainless steel powder metallurgy, appropriate strengthening phase can be added, especially the mechanical properties. Taking 316L stainless steel as an example, 1.5%-3% silicon carbide is added to the stainless steel. Due to the interaction between silicon carbide and stainless steel, a low melting point phase is formed, which increases the density of the sintered body and improves the hardness and wear resistance of the sintered body.

(3) In the process of powder pre-mixing, due to the different proportions of particles of different components, segregation will occur during the powder mixing process. The binder can effectively improve the segregation. Due to the different particle sizes in the powder, the uneven distribution will easily lead to an increase in porosity. The binder can make the particles reasonably distributed, fill the pores, and improve the strength of the green compact.

Tianshi PEW-0301 is a powder metallurgy premixed binder with the following characteristics:

① Effectively prevent the segregation of components caused by the difference in specific gravity of the particles.

② Reasonably distribute the distribution of large and small particles to improve the density of the green compact.

③ Improve the strength of the green compact.

④ Less dust pollution in the feeding process.

Post Casting Process

1. Heat treatment: annealing, carbonization, tempering, quenching, normalizing, surface tempering

2. Processing equipment: CNC, WEDM, lathe, milling machine, drilling machine, grinder, etc.;

3. Surface treatment: powder spraying, chrome plating, painting, sandblasting, nickel plating, galvanizing, blackening, polishing, bluing, etc.

Moulds and Inspection Fixtures

1. Mold service life: usually semi-permanent. (except for lost foam)

2. Mold delivery time: 10-25 days, (according to product structure and product size).

3. Tooling and mold maintenance: Zhongwei is responsible for precision parts.

Quality Control

1. Quality control: the defective rate is less than 0.1%.

2. Samples and trial run will be 100% inspected during production and before shipment, sample inspection for mass production according to ISDO standards or customer requirements

3. Testing equipment: flaw detection, spectrum analyzer, golden image analyzer, three-coordinate measuring machine, hardness testing equipment, tensile testing machine;

4. Provide after-sales service.

Application

Powder metallurgy has unique chemical composition and mechanical and physical properties that cannot be obtained by traditional melting and casting methods. Using powder metallurgy technology can directly make porous, semi-dense or fully dense materials and products, such as oil-impregnated bearings, gears, cams, guide rods, tools, etc., is a less cutting process.

Stainless steel powder metallurgy sintered parts related enterprises are mainly applicable to the production and research of spare parts in the fields of automobile industry, equipment manufacturing industry, metal industry, aerospace, military industry, instrumentation, hardware tools, electronic appliances, etc., production of related raw materials and accessories , All kinds of powder preparation equipment, sintering equipment manufacturing. Products include bearings, gears, carbide tools, molds, friction products and more.