Study on High-Temperature Mechanical Properties of SPHC Steel Produced by CSP Technology

The high-temperature mechanical properties of SPHC steel produced by compact strip production (CSP) process were tested on Gleeble thermal simulator under different temperature conditions. The results show that: at the strain rate of 1×10-3s-1,the SPHC steel has three brittleness temperature zones within the range from 650°C to 1200°C;the percentage reduction of area of the tested steel are all above 60% within the range from 950°C to 1150°C,thus the steel has good high temperature plasticity; the percentage reduction of area decreases rapidly when the testing temperature is under 900°C and the minimum percentage reduction of area is only about 41.78% at 800°C.

Study of Deoxidization and Desulphurization in Slag Washing Process of Al-Killed Steel

In order to reduce the production cost, In one factory product the SPHC steel of general requirements using slag washing process （BOF→Slag washing oxygen alloying→Ladle argon-blown→CC）, the system study was analyzed about deoxidization and desulphurization behavior of slag washing process. The results of the study show that, when the content of Als 300~500ppm, dissolved oxygen 3~6ppm, the steel desulfurization rate remains stable at 35% to 48%, the average desulfurization rate is 42%. The process of the [N] content, increasing [S] are lower than the LF refining, the operation is simple and can meet the metallurgical requirements.

Study on Process of SPHC Steel Solidification

Confocal Laser Scanning Microscopy in situ observation of the solidification process of SPHC Steel and SPHC steel solidification structure changes. The results showed that: SPHC steel in the molten state, the surface of the melt flow of black substance; and with the temperature decreasing, SPHC gradually solidified dendrites continue to grow, increasing new nuclear the dendritic structure continue to refine, to δ-Fe and γ-Fe crystalline phase from the melt.