Molding methods of metal products are popular, and the porosity rate of bricks is about 20%-50%. In order to get low-porosity metal products, they are sintered from green bricks. We can use sintering method to reduce the porosity to a certain value, and it is possible that we can make metal products get within ideal density range.
Molding pressure and temperature restrict the service life of metal products. Now we most use graphite molding method, and the molding pressure is between 10-15 MPa. Besides, we can use titanium carbide molding method, when the temperature is between 800-900℃,the pressure is between 14-21 MPa.
Generally, tig welding can be divided into three steps. During hot-press process, the enlarge of certain particles can increase viscosity and decrease density. So in burdening before molding, we should properly add inhibitors to reduce the growth speed of particles. Compared with sintering metal products, hot-press insulating bricks have high strength and thermal conductivity. Besides, hot-press metal products have low shock resistance.
Besides, tig welding can be divided into different types, such as dynamic hot-press, reactive hot-press, thermal static hot-press and carbon oxide hot-press. Among them, thermal static hot-press can produce complex compact metal products. And it is recognized as a promising method of manufacturing metal products. Though hot-press have more potentials than common sintering, it need more complicated devices.
Above is tig welding of metal products.