Torsion Test, as a Method for Measuring Toughness of Grey Cast Iron

Abstract

Various cast irons, having different types of graphite such as A.D.E etc (ASTM-chart), were prepared. The toughness of cast iron was measured by the three different methods: (1) Tensile test, where the elongation is measured precisely by Marten’s extensiometer. The toughness is expressed by the resilience which is calculated from the area covered by stress-strain curve. (2) Torsion test. The resilience is calculated from the curve of twisting morment and twisting angle. (3) Charpy impact test. The following results were obtained. (1) As to the toughness of cast iron, the three methods have shown good agreement. (2) Torsion test is very practical, as it can be carried more easily than the precise tensile test.