تاثير فرايند ذوب و عناصر آلياژي بر ساختار و خواص آلياژمونل پايه 40Cu-60Ni در شرايط كار شده

Effect of Melting Process and Alloying Elements on Structure and Properties of the Wroughted 60Ni-40Cu Base Monel Alloy

In this research the effect of inert and vacuum atmospheres in melting and casting process on decreasing 0 and N gases, the effect of ESR process and alloying elements in Range of38-42% Cu, 0.2-1.0% Fe, 1.2-2.2% Mn, 0.01-0.3% C, on structure, hardness, tensile properties and electrical resistance of a 60Ni-40Cu alloy was investigated. The results show that vacuum induction melting (VIM) reduce oxygen content about 53% relative to Ar atmosphere. This increases strength and ductility and decreases electrical resistance of the alloy. In addition, ESR process improves hardness, tensile properties and reduces electrical resistance because of elimination of casting defects, melt refining and fine dendrite structure. Under 70 percent hot work and annealing condition, decreasing in Cu and increasing in Fe, Mn and C leads to improve strength, deteriorate ductility and higher electrical resistance. Under 80 percent cold work and annealing condition, decreasing in Cu and increasing in Fe and Mn, the same result occurs. But increasing in C leads to decrease of hardness and tensile properties because of graphite precipitation extended in the milling direction.