To provide a material having high notch impact value and ductility, and excellent chemical properties regarding high temperature corrosion or heat corrosion.

A Cr-Ni-based alloy material used for manufacturing a half-finished product as a starting material especially for forming a composition part 1 of a large diesel engine is represented by (Cr_xNi_yA_z)N_k, where x+y+z+k=100%, a component A is one or more kinds of elements selected from chemical elements, La, Ce, Y, Hf, Sc, Si, C, S, P, Al, Zr, B, Mo, Fe, Mn, O and rare earth elements, the Cr amount x is, by weight, 50%<x<100%, the Ni amount y is, by weight, y>0%, the amount z of the component A is, by weight, 0%≤z<50% and the nitrogen content k is, by weight, 0.01%≤k≤0.1%.