Mechanical Properties of Arc‐Cast and Powder Metallurgy Molybdenum

Abstract

Having found that molybdenum can be so wrought and annealed as to have high ductility when fully recrystallized, an effort was made to make a comparison in this preferred condition of one lot of molybdenum as consolidated by powder metallurgy methods with another lot consolidated from powder by arc casting. The results show‐very little difference between these products in tensile properties determined over a range of temperatures above and below atmospheric or in creep strength at 1600°F. Particularly significant is the finding of a well‐defined transition between ductile and brittle fracture on tensile test at a temperature only slightly below atmospheric which is similar to that occurring in iron at lower temperatures.The fine‐grained, fully recrystallized condition in pure molybdenum is unfavorable to creep strength as it is known to be in other pure metals, but its creep strength is remarkably high relative to other pure metals of lower melting point and even to alloys of the same.