HEAT-RESISTANT WROUGHT WELDABLE ALLOY FOR GTE COMPONENTS WITH LOW LINEAR THERMAL EXPANSION COEFFICIENT

摘要

Features of the effect of alloying elements on linear thermal expansion coefficient of wrought heat-resistant alloys based on the Ni-Fe system are studied. Short-term and long-term strength at 600°C is simulated and parameters are used successfully as equivalent alloy chemical composition, calculated by a system of unpolarized ionic radii equations. A new deformable weldable alloy based on Ni-Fe-Co is developed with working temperature up to 650°C, with σ_u~(20) = 1400 MPa, σ_u~(600) = 1200 MPa, and σ_(100)~(600) = 950 MPa, with low linear thermal expansion coefficient (α = 11.8-10~(-6) K~(-1) in the temperature range 20-600°C). The alloy-is structurally stable, efficient in forming and welding, and with respect to set of properties it is belter than standard alloys of similar designation. New alloy structure, phase composition, and properties are described.