Patent ID: 6123898
Filing Date: 2000-09-26
Classification: C22C,H01M,Y02E

Abstract:
A low thermal expansion alloy comprising Cr--W--Fe based alloy selected from the groups consisting ofCr--W--Al--Fe, Cr--W--Al--B--Fe, Cr--W--Al--M--Fe, Cr--W--Al--B--M--Fe, Cr--W--Co--Fe, Cr--W--Co--B--Fe, Cr--W--Co--M--Fe, Cr--W--Co--B--M--Fe, Cr--W--Co--Al--Fe, Cr--W--Co--Al--B--Fe, Cr--W--Co--Al--M--Fe, Cr--W--Co--Al--B--M--Fe, Cr--W--(Ti, Zr, Hf)--Fe, Cr--W--(Ti, Zr, Hf)--B--Fe, Cr--W--(Ti, Zr, Hf)--M--Fe, Cr--W--(Ti, Zr, Hf)--B--M--Fe, Cr--W--(Ti, Zr, Hf)--Al--Fe, Cr--W--(Ti, Zr, Hf)--Al--B--Fe, Cr--W--(Ti, Zr, Hf)--Al--M--Fe, Cr--W--(Ti, Zr, Hf)--Al--B--M--Fe, Cr--W--(Ti, Zr, Hf)--Co--Fe, Cr--W--(Ti, Zr, Hf)--Co--B--Fe, Cr--W--(Ti, Zr, Hf)--Co--M--Fe, Cr--W--(Ti, Zr, Hf)--Co--B--M--Fe, Cr--W--(Ti, Zr, Hf)--Al--Co--Fe, Cr--W--(Ti, Zr, Hf)--Al--Co--B--Fe, Cr--W--(Ti, Zr, Hf)--Al--Co--M--Fe and Cr--W--(Ti, Zr, Hf)--Al--Co--B--M--Fe,the low thermal expansion alloy having limitations for each alloying element comprising 15-40 wt % of Cr, 5-15 wt % of W, 0.1-1 wt % of Al, 1-10 wt % of Co, 0.1-5 wt % of at least one element selected from Ti, Zr and Hf, 0.001-0.01 wt % of B, 0.01-1 wt % of M which is at least one element selected from Y, Hf, Ce, La, Nd and Dy and the balance being Fe and unavoidable impurities, wherein when Hf among Ti, Zr and Hf is solely used, the alloy can contain 1 to 5 wt % of Hf and only when at least one element out of Ti and Zr is used, Hf can be selected as M.