Nitrogen oxides (NOx) are important atmospheric pollutants that can cause environmental problems such as acid rain and photochemical smog, as well as direct damage to the human respiratory system. In addition, it also has an important contribution to the increasingly serious ash pollution in our country. Therefore, effective control of NOx emissions is a major strategic need in China.

High specific gravity tungsten-based alloys are mainly composed of nickel, iron, cobalt, copper, chromium and other elements. The existing methods of preparing tungsten-based alloy materials are usually powder injection moulding, mainly using wax matrix system to make powder injection moulding.

Ceramic material is one of the most promising materials because of its excellent properties such as high temperature resistance, corrosion resistance and wear resistance. However, the brittleness of ceramic materials has been restricting its further development.

Electric contacts are the core components of low-voltage electrical appliances. They take on the task of switching on and off the circuit in various control switches. They are widely used in military, aviation, aerospace and industrial control fields. The electrical properties of silver-based contact materials have a vital impact on the long life and high reliability of various electronic control systems.