Hardening of the sheave

Flame Harden Steel 1045 is pretty good.  Expect 50-55 Rockwell C.

Vacuum hardening 1045.  The entire piece is heated up, therefore, the entire piece will be hardened throughout and then it is quenched in an inert gas.  Similar hardness to flame hardening. Expect 50-55 Rockwell C.  The sheave will be bright and shiny.

• No Discoloration: In a vacuum, there aren’t any impurities that can cause the metal to get scalded or discolored.
• Avoid Oxidation: In a vacuumized environment, the absence of air prevents oxidation, preserving the metal’s surface finish while aging.
• Improved Properties: Vacuum hardening not only avoids damage but also enhances several material properties.

During vacuum hardening, material is heated in the absence of oxygen by convection in the medium of inert gas (N2) and / or heat radiation in the vacuum atmosphere. Steel is hardened with a stream of nitrogen, whereby cooling rate can be determined by selecting the excess pressure. Depending on the workpiece shape it is possible also to choose the direction and time of nitrogen blowing. Optimization of time and steel temperature control are carried out during process.