The application of vacuum degassing to bearing steel
The transition from air melted steel to carbon-dioxidized, ladle vacuum degassed steel for bearings has been accomplished smoothly. An improvement of bearing life ratings has developed simultaneously with the use of vacuum degassed steel. Through-hardening 52100 bearing steel produced by ladle vacuum degassing shows improved microcleanliness. The most noticeable effect of this degassing practice on the microcleanliness of 52100 is the reduction in size and frequency of D-type globular oxides and the increase in sulfide ratings. Micro-probe and metallographic investigations have shown that sulfides are associated with D-type oxide inclusions in air melt 52100; however, this is not the case for 52100 VP. This results in the presence of greater numbers of sulfides in the degassed steel. Degassing practice has now developed to the stage where steel compositions tailored to this process are desirable.
Unable to display preview. Download preview PDF.
- 1.J. D. Murray and R. F. Johnson: Special Report 77 on Clean Steel, Iron and Steel Inst., London, 1963, pp. 110–118.Google Scholar
- 2.L. O. Uhrus: Special Report 77 on Clean Steel, Iron and Steel Inst., London, 1963, pp. 104–109.Google Scholar
- 3.R. F. Johnson and J. F. Sewell: J. Iron and Steel Inst., December 1960, pp. 414–443.Google Scholar
- 4.E. Harness: Private communication.Google Scholar
- 5.T. E. Perry: High Vacuum Degassing—The Process and The Results, paper presented at General Meeting of American Iron and Steel Inst., New York, May 26, 1965.Google Scholar