Metallurgy

Powder metallurgy mainly consists of four processes, traditional method PM, metal injection molding (MIM), metal additive manufacturing (MAM), isostatic pressure(IP), the traditional PM and MIM method are the most commonly used technologies.

Traditional PM (also called sintered metal parts)
Powder metallurgy process can be used for manufacturing materials, such as refractory metals and carbide. Sintered metal parts can directly be pressed to final product size. Thereby it minimize the subsequent machining needs, saves material usage, reduces production costs, eliminates need for melting materials, reduces impurities and material oxidation to improve material purity.

Metal Injection Forming (MIM)
The mechanical properties of parts produced by metal injection molding process, is almost equivalent to forged materials. Besides high production rates, MIM also provides the ability to form almost unlimited shapes and geometric features. While it suits small, generally less than 250g, as well as complex parts. MIM technology has obvious advantages over other forging technologies: 95% material utilization rate, saving about 60% energy consumption, highest accuracy of 0.01mm, minor size difference between parts, mass production for complex structural parts, more uniform composition, no bubbles, no impurities and other problems.

Powder metallurgy, as a scalable technology, continues to expand its applications into other process categories, e.g. powder metallurgy companies can make gear components for automotive engines and transmissions, components for new energy vehicles, such as electric vehicle transmission systems, fuel cell connecting boards and etc. Various raw materials can be used for powder metallurgy, such as magnetic materials, which can be used in on-board chargers, charging piles, photovoltaic, solar energy and other new energy fields.

Generally, powder metallurgy can be used for following:
● To produce porous product and bearing for automobiles
● To produce oil pump gears for automobiles
● Production of cutting tools, wire drawing dies and deep drawing dies
● To produce refractory metal composites, e.g. tungsten, molybdenum, tantalum for manufacturing the tungsten wires for filaments in the lamp industry
● Diamond impregnated tools are produced by a mixture of iron powder and diamond dust.
● To produce electrical contract materials, e.g. circuit breakers, relays and resistance welding electrodes
● Parts of cars, aircraft, gas turbine, electric clocks and etc.
● Parts of vacuum cleaners, refrigerators parts of guns, sewing machines

The downstream industries of powder metallurgy can be auto parts, motorcycle accessories, compressor accessories and other accessories industries. In 2019, the proportion of these industries are as follows: automotive takes 50%; motorcycle takes 10%; power tools takes 25%; agricultural machinery parts occupies 3%; engineering machinery parts occupies 6%; others occupies 6%.

From the global powder metallurgical market perspective, the largest sales market is automotive industry, which has 350 auto parts applications and requires highest quality. In automotive applications, 75% parts are for engines and transmissions, pipes, seat, linkage, bearing seat, key components of variable valve timing system (VVT) and exhaust support spline; others for chassis, shock absorber parts, guides, pistons and low seat, ABS sensors, brake pads and etc. In brake system, pump parts is key component in fuel pumps, oil pumps and transmission pumps.
By product, the application of powder metallurgical parts in engines and automatic transmissions has increased significantly because of 2 reasons: 1) cost-effective performance of powder metallurgical parts, 2)complex structural parts can be manufactured and reliable electrical pulses can be used to improve the electronic control of the engine.

In medical industry, PM application can greatly meet human’s compatibility, non-corrosive and high wear resistance requirement. Comparing to MIM and 3D metal printing techniques (additive manufacturing) that produce complex geometry with titanium alloys, nickel alloys, stainless steel and more materials, it is difficult to manufacture required parts if adopting traditional processes. Surgical instruments, especially those used in laparoscopic surgery, require complex design and elaborate small to miniature size components. MIM (Metal Injection molding) technology produces a large number of ingredients with high quality. Non-corrosive materials are fully suited to maximum durability and long life cycles. When surgical instruments are manufactured with MIM technology, the sharpness of the cutting edge can be increased greatly. Plastic surgery has extremely high request for reliability, functionality and aesthetics. And MIM technology can be used in artificial knee limb parts manufacturing to ensure high load capacity; MIM materials are fully compliant with required durability, non-corrosive and high surface quality. MIM technical support any 3D shape to maximize the functionality and light weigh requirements.

Lightweight fuel-saving requirement drives PM applications in aerospace Hot Isostatic Pressure (HIP) technology to meet demanding requirements of lightweight and high strength for aerospace parts. Aircraft requires minimized fuel costs, pressure, greenhouse gas emissions. And it also needs more efficient engines with high-strength materials so as to operate at higher temperatures. The aerospace industry needs to meet increasingly demanding by developing new materials and processes in the field of powder metallurgy. PM has advantages in repair technology, 3D metal printing technology and HIP, and it continues to provide more powder metallurgical material applications for aerospace.

Applications for technology in next 10 years include energy, medical devices, aerospace, electrical, electromagnetic and defense. Among these industries, energy, healthcare and aerospace industries ranks top three. New green energy demand drives PM's new application to fuel cell plates, which requires porous structure and composite materials and it also reduces costs effectively.

By the end of 2019, there had been about 2000 powder metallurgy manufacturers, high end, middle end and low-grade in China. Low end suppliers mainly produce for consumer electronics, home appliances powder metallurgy products. Most of these suppliers have 20 to 100 people and their management system is not sound. Mid-end suppliers have 100 to 200 employees. They have management system and can produce automotive parts with low requirements. Some of them have IATF16949 certification. High-grade suppliers, who have strong capability to take export orders, always have more than 200 employee.

1. The technical requirement of powder metallurgy parts in the home appliance and consumer electronics industry is low. Thus most small and medium-sized manufacturers compete in these area.
2. In developed countries, such as the United States, countries of Europe, Japan, powder metallurgy products are mainly used in automotive field. Automotive powder metallurgy products, account for more than 80% of the total products of powder metallurgy, including VVT (variable valve timing system), VCT (variable valve camshaft timing system), various types of pump components, sprockets, synchronous ring, planetary gears and etc. However, China's domestic automotive powder metallurgy products account for only about 60% of the total products of powder metallurgy. At the same time, China's automotive powder metallurgy manufacturers mainly provide some low-tech linkage, gaskets, sprockets and other products. And the vast majority of companies can not launch mass production for higher technical requirements of VVT, VCT, planetary gears and other products.
3. However, parts produced by domestic powder metallurgy companies have significant cost advantages and broad growing space comparing with import parts. In contrast with foreign companies, domestic powder metallurgy companies have advantages in terms of labor costs, land costs, raw material costs and etc. At the same time, domestic powder metallurgy suppliers have short delivery cycle, timely after-sales service and could provide better service.