By Kari Williamson

The technology allows drivetrain components such as gears that require precision and durability to be made using sintered alloys instead of the current cutting processes.

The powder-metallurgy process reduces waste of materials and energy consumption while manufacturing mechanical components as a means of addressing recent environmental and energy issues, NTN says.

Previously sintered alloy methods has often led to micropores developing inside components, resulting in decreased fatigue characteristics compared to components manufactured using cutting process of solid metals, but NTN's method is said to have overcome this problem.

NTN has made improvements to the powder material, forming and sintering conditions to manufacture high-density sintered compact with an absolute density of ratio 95% or higher, using a relatively low casting pressure of 6 to 10 tonnes/cm2.

The combination with NTN's heat treatment technology results in an endurance strength of 300 MPa or higher under single press, single sintering process.

When used for gears, this high endurance strength results in 2 GPa or higher strength (1.5-times conventional products) at the tooth surface, as well as better durability at the base of the tooth, the company says.

Different combinations of technologies such as metal powder, forming and heat treatment allow high-precision, high-density sintered alloys to be manufactured with a much easier process, making use of alloys in drivetrain components and other applications.

NTN says it will coordinate with group company Nippon Kagaku Yakin Co Ltd to accelerate the development of products using sintered alloys, as well as the research and development of stronger, higher precision sintered alloys or composite materials.