Muffle furnace heat treatment operation process

The muffle furnace heat treatment furnace is a comprehensive process in which materials are heated, insulated and cooled in a certain medium, and their performance is controlled by changing the surface or internal structure of the material.

Common processing method of muffle furnace:

1: Muffle furnace annealing: refers to a heat treatment process in which metal materials are heated to an appropriate temperature, kept for a certain period of time, and then slowly cooled. Common annealing processes are: recrystallization annealing, stress relief annealing, spheroidizing annealing, complete annealing and so on. The purpose of annealing: mainly to reduce the hardness of metal materials, improve plasticity, to facilitate cutting or pressure processing, to reduce residual stress, to improve the uniformity of structure and composition, or to prepare for the subsequent heat treatment.

2: Muffle furnace normalizing: refers to the process of heating steel or steel parts above or (the upper critical point temperature of steel), keeping it at 30～50℃ for an appropriate period of time, and then cooling it in still air. The purpose of normalizing is to improve the mechanical properties of low-carbon steel, improve machinability, refine grains, eliminate structural defects, and prepare for the subsequent heat treatment.

3: Muffle furnace quenching: refers to heating the steel to a temperature above Ac3 or Ac1 (the lower critical point temperature of steel), keeping it for a certain period of time, and then obtaining martensite (or bainite) at an appropriate cooling rate ) The heat treatment process of the organization. Common quenching processes include salt bath quenching, martensite graded quenching, bainite austempering, surface quenching and partial quenching. The purpose of quenching: to obtain the required martensite structure of the steel, improve the hardness, strength and wear resistance of the workpiece, and prepare the structure for the subsequent heat treatment.

4: Muffle furnace tempering: refers to the heat treatment process in which steel parts are quenched and then heated to a certain temperature below, kept for a certain period of time, and then cooled to room temperature. Common tempering processes are: low temperature tempering, medium temperature tempering, high temperature tempering and multiple tempering. The purpose of tempering: mainly to eliminate the stress generated by the steel during quenching, so that the steel has high hardness and wear resistance, and has the required plasticity and toughness.