PTC has undergone massive growth in evolution of new melting, re-melting and casting technologies under vacuum. This development has been driven by various factors, and is also focused on the increasing demand from the aerospace and power turbine sectors.
Critical components in higher alloys have a high affinity for oxygen, nitrogen and hydrogen an cannot be melted or poured in ambient conditions as formation of oxides and/or nitrides will occur which influence the mechanical properties of the material. Hence, Nickel-based superalloys contain many volatile and reactive elements and also require melting and pouring under vacuum conditions. Titanium and Zirconium are labelled “reactive metals” because they very rapidly react with oxygen and/or nitrogen to form refractory compounds. Melting of reactive metals involves protecting the molten metal from sources of nitrogen and oxygen. To minimize or avoid the formation of inclusions, vacuum melting becomes essential. Therefore, the following vacuum melting capabilities are available: