PRIOR AUSTENITE GRAINS IN STEELS LASER-SURFACE ALLOYED WITH CARBON

Prior austenite grain size is known to affect the hardness of martensi te in conventional martensitic hardening of steels. These grains devel op in solid state during austenitizing treatment. In the present study , however, it is pointed out that the prior austenite grains that form as a result of solidification in laser surface hardening of steels by alloying with carbon should have similar effects on the resultant mar tensite in the alloyed layer. A low alloy steel and a commercial pure iron have been laser surface alloyed with carbon to show the solidifie d austenite grains in the alloyed layer. (C) Elsevier Science Inc., 19 97.