TEM STUDIES OF NITRIDES IN SURFACE-TREATED AND IMPLANTED 12-PERCENT CHROME STEEL

Specimens of alloy steel containing 12% chromium as a major alloying constituent were implanted with 100 kev N//2** plus ions at a cosntant fluence of 1 multiplied by 10**1**7 N//2** plus cm** minus **2. The estimated specimen temperature during implantation did not exceed 450 K. Two kinds of specimens were used for implantation: electropolished and mechanically polished. Iron nitrides of the Fe//1//6N//2 type and mixed iron chromium nitrides (Cr,Fe)//2N//1// minus //x (x equals 0-05) were found in electropolished samples. In mechanically polished samples the Fe//1//6N//2 nitrides predominated. The influence of markedly different surface layers on nitride formation and their detection by diffraction methods is discussed.