Powder Metallurgy Pressed Parts

The pressing methods of Powder metallurgy pressed parts are one-way pressing and two-way pressing. Because of the different pressing methods, the internal density distribution of the product is different. In simple terms, for unidirectional pressing, the pressing force decreases with the distance from the punch due to the friction of the inner wall of the die, and the density varies with the pressure. Lubricants are generally added to the powder to facilitate pressing and demolding. The lubricant reduces the friction between the powders during the low-pressure stage of the pressing process and rapidly increases the density. However, in the high-pressure stage, since the lubricant is filled in the gaps of the powder particles, On the contrary, it hinders the density of the product. The control of the demoulding force of the product avoids the surface defect of the product caused by the demolding process.

During the pressing process, the weight of the product must be confirmed, which is very critical, because the air pressure in many factories is unstable, which will lead to a large difference in the weight of the product, which directly affects the performance of the product.

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.

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.

Steps of powder metallurgy pressed parts

The processing process of Powder metallurgy pressed parts is divided into four steps, firstly, the preparation of powder involves the preparation of materials, according to the requirements of the materials, the ingredients are prepared according to the formula, and then the mixture is mixed. The method mainly considers the particle size and flowability of the powder and the bulk density. The particle size of the powder determines the gaps to fill in the particles, use the mixed materials immediately, do not leave them for too long, it will cause moisture and oxidation.

The second is to press the powder. There are two main pressing methods commonly used in the powder metallurgy process, namely unidirectional pressing and bidirectional pressing. Due to the different pressing methods, the internal density distribution of the product is also different. In simple terms, for unidirectional pressing, as the distance from the punch increases, the friction of the inner wall of the die reduces the pressure, and the density changes with the pressure.

Lubricants typically need to be added to the powder next to facilitate compaction and demolding. The lubricant reduces the friction between the powders in the low pressure stage and increases the density rapidly; but in the high pressure stage, because the lubricant fills the gaps between the powder particles, it will hinder the density of the product instead. Controlling the release force of the product avoids surface defects caused by the demolding process.

During the pressing process of powder metallurgy, it is necessary to confirm the weight of the product, which is very critical, because the unstable pressure in many factories will cause the weight difference to be too large, which directly affects the performance of the product. The pressed product must be blown off the powder and impurities remaining on the product surface, neatly placed in the appliance, and protected from impurities.

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 pressed parts can be used in the following fields:

1. Hardware field: There are locks, hardware tools, and power tool spare parts that use powder metallurgy processing technology.

2. Medical equipment collar: There are medical forceps, surgical forceps, and various medical equipment spare parts that use powder metallurgy processing technology.

3. In the field of home appliances and electronics: there are a variety of home appliances, mobile phones, notebooks, smart wear and other product parts that use powder metallurgy processing technology.

4. Application products in the automotive field: parts including automotive gears, automotive wiper parts, automotive tailgate parts, automotive compressor parts and other parts are all made of powder metallurgy processing technology.

5. Communication field: Communication base station antenna parts, gear boxes and other products all use powder metallurgy processing technology.

Powder metallurgy process is a forming technology, near net forming and rapid prototyping. Compared with traditional forming processing technology, it saves materials and costs, has higher efficiency, and has better quality and effect. Therefore, it is currently available in various fields. applications, including aviation.