Influence of long-term heating on the fatigue properties of low-alloyed cast steel STN 42 2707

Abstract

In this paper the authors publish own experimental results of examination of low-alloyed cast steel STN 42 2707 fatigue properties (near- threshold regime of fatigue crack propagation for rates from da/dN =5.6x10-9m.cycle-1to da/dN =10-12 m.cycle-1 and Kath at da/dN =10-12 m.cycle-1) initial state and after long-term heating (T = 400 °C, t = 4000 hours ≈ 167 days) obtained at high-frequency loading (f ≈ 20 kHz, T = 20 ± 5 °C, R = -1). The long-term heating of material caused decrease of Kath and increase of fatigue crack growth rate in the near-threshold regime; then worse of low-alloyed cast steel STN 42 2707 fatigue properties.

Keywords

• cast steel STN 42 2707
• long-term heating
• fatigue properties
• Kath
• da/dN = f(Ka)