The effect of boron on the thermal fatigue behavior of Iron-chromium-carbon-silicon alloy

The effect of boron on the thermal fatigue behavior of Fe-20Cr-1.7C-1.0Si-xB (x = 0, 0.3 and 0.6 wt.%) hardfacing alloys was investigated using a high frequency induction heating/water cooling system. Formation and growth of thermal fatigue cracks in tested alloys was also investigated, and the effect of the strain-induced martensitic transformation on cracking was analyzed by means of optical microscopy and by nondestructive testing using ultrasonic elastic waves. These experiments demonstrated that the alloy exhibits sustained resistance to thermal fatigue in its early stages since the strain-induced martensitic transformation interfered with the propagation of fatigue cracks.