Abstract: The invention relates to a cast-iron alloy comprising (in wt %) C: 3.0-3.5 Si: 4.1-4.8 Mn: ?0.4 Mg: 0.02-0.08 Cr: 0.4-1.0 Cu: ?0.15 Mo: 0.8-1.2 P: <0.05 S: <0.015 the remainder comprising Fe and any impurities. The invention relates also to an exhaust-conducting component for truck engines which comprises the alloy according to the invention.

Abstract: The invention relates to a grey iron alloy having (in wt %): C: <4.2% Si: <1.30% Mn: 0.4?0.8% Nb: 0.05?0.4% Cr: <0.4% Cu: <0.7% V+Ti+Mo: <0.4% P: <0.05% S: <0.1% the remainder having Fe and naturally occurring impurities, and the degree of saturation Sc, expressed as % C/(4.26?0.317*(% Si)+0.027(% Mn)?0.3(% P))>1.

Abstract: A method for determining fatigue strength of engine components, comprising the steps of -providing an engine component, -loading at least part of the component to a level below its tensile strength and measuring its resulting deformation, -determining at least one magnitude on the basis of the load applied and the deformation measured, -providing a predetermined relationship between measured fatigue strength of components and the aforesaid at least one magnitude determined on the basis of the ratio between load applied to engine components and their deformation, -determining the fatigue strength of the engine component provided,on the basis of the at least one magnitude determined and the predetermined relationship.