The Bending Strength and Fracture of High Carbon High Vanadium Iron Alloys

Abstract

Micro-bending test and microscopic examination were carried out on high carbon high vanadium iron alloys prepared by melting and by over-laying method, in order to study the effects of size and distribution of V-carbide on the bending strength of the alloy. V-carbides in the specimens were controlled from 21 to 55% in volume and from 2 to 100 μm in diameter, dispersing in matrix of the ferrite, austenite and martensite. It was observed that cracks originated in the carbide phases due to a stress concentration, and was propagated iuto the matrix. The strength of the alloy was more in fluenced by the size than the amouut of the carbide. The cleavage fracture occurred partly in alloys containing much amount of V-carbide, even if the matrix was fully annealed.