“…11,19,[43][44][45][46][47][48] The degree of reduction varies, however, strongly from machine to machine, from 2 to 9 for carbon and from 3 to 15 for oxygen, depending on particular conditions, e.g., the gas composition used for boronization, the quality of covering produced, etc. Henceforth, we assume in our calculation that the erosion yields Y C and Y O are reduced after boronization by an averaged factor of 5, however, the results do not noticeably change if the reduction factor is 4 or larger.…”