Study on the diffusion behavior between NiAlCoCr nickel-based alloy and high entropy alloys

By combining solid-state diffusion couple experiments with a numerical inverse method, the interdiffusion coefficients in NiAlCoCr/CoCrFeMn 0.2 Ni and NiAlCoCr/CoCrCu 0.2 FeNi diffusion couples were determined at 1,273–1,373 K, and their reliability was verified. The main interdiffusion coefficients on the NiAlCoCr alloy side were greater than those on the high-entropy alloy side at 1,273–1,373 K. The main interdiffusion coefficients followed the trend: <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mrow> <m:msubsup> <m:mover accent="true"> <m:mi>D</m:mi> <m:mo>˜</m:mo> </m:mover> <m:mtext>MnMn</m:mtext> <m:mtext>Ni</m:mtext> </m:msubsup> </m:mrow> </m:math> DMnMnNi > <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mrow> <m:msubsup> <m:mover accent="true"> <m:mi>D</m:mi> <m:mo>˜</m:mo> </m:mover> <m:mtext>CuCu</m:mtext> <m:mtext>Ni</m:mtext> </m:msubsup> </m:mrow> </m:math> DCuCuNi > <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mrow> <m:msubsup> <m:mover accent="true"> <m:mi>D</m:mi> <m:mo>˜</m:mo> </m:mover> <m:mtext>CrCr</m:mtext> <m:mtext>Ni</m:mtext> </m:msubsup> </m:mrow> </m:math> DCrCrNi > <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mrow> <m:msubsup> <m:mover accent="true"> <m:mi>D</m:mi> <m:mo>˜</m:mo> </m:mover> <m:mtext>FeFe</m:mtext> <m:mtext>Ni</m:mtext> </m:msubsup> </m:mrow> </m:math> DFeFeNi > <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mrow> <m:msubsup> <m:mover accent="true"> <m:mi>D</m:mi> <m:mo>˜</m:mo> </m:mover> <m:mtext>CoCo</m:mtext> <m:mtext>Ni</m:mtext> </m:msubsup> </m:mrow> </m:math> DCoCoNi at 1,273 K. Tracer diffusion coefficients were calculated for both the CoCrFeMn 0.2 Ni/NiAlCoCr and CoCrCu 0.2 FeNi/NiAlCoCr diffusion couples at 1,273–1,373 K. Furthermore, the composition-dependent diffusion activation energies of the tracer diffusion coefficients were analyzed in the CoCrCu 0.2 FeNi/NiAlCoCr diffusion couple.