TI-AL BASE ALLOY MATERIAL EXCELLENT IN WEAR RESISTANCE, MANUFACTURE THEREOF AND METHOD FOR HARDENING SURFACE OF SUCH ALLOY

摘要

PURPOSE: To form a hardened layer with an excellent wear resistance, high- temperature acid resistance and corrosion resistance by heating under a high vacuum a titanium alloy casting containing a specific quantity of aluminum and applying a dealuminization treatment on the surface layer. ;CONSTITUTION: On the surface of a base material that consists of Ti-Al based alloy containing 30-36wt.% or desirably 32-34wt.% of Al, a wear resistant hardened layer is formed which is harder than the base material and which contains Al of 27wt.% or less in Ti(n)Al ((n) denotes 1(n)≤3). This wear resistant hardened layer is formed by heating the alloy in the degree of vacuum at 1×10^-3Torr or less and in the temperature range of 1,100-1,450°C and carrying out dealuminization. Desirably, the degree of vacuum at the heating is made 10^-4Torr or less, and the heating temperature in the range of 1,100-1,300°C. This base material of Ti-Al based alloy is provided with a superior ordinary- temperature ductility; and it is desirable to micronize crystalline particle size by further adding B of 0.4wt.% or less.;COPYRIGHT: (C)1996,JPO