The significance of using ultra-low temperature deep cold destressing furnace treatment

ultra-low temperature deep-cold destress furnace
using industrial chillers for heat treatment methods are mainly common heat treatment and surface heat treatmentOne of the wideapplications is mainly ordinary heat treatmentThe common heat treatment of chillers mainly includes: annealing, positive fire, quenching and temperingfire1, completely annealing for medium and low-carbon steel heating to a full O's state, chiller temperature is Ac3 (refers to the phase change temperature of sub-polysist steel) above 30 to 50 degrees C, heat ingon after a certain amount of time to cool to room temperature, to obtain close to the balanced state of the tissue heat treatment processMainly applicable to sub-common steelThe aim is to improve machining performance by eliminating surface hardening of forgings and castings, reducing hardness and eliminating residual stressthe soluble sequester formed by carbon dissolved in iron is called the AusteriaThe solubility of the chiller carbon in the Austeria body is greater than in the carbon body (2.06% at 1147 degrees C and the hardness is HB 160-200)The low temperature of the stable Aumersis is 723 degrees C, i.eit is present in the high temperature region, and the plasticity is goodThe pressure processing state of the vast majority of steel species is also the state of the steel when heating for heat treatmentWhen the temperature is below 723 degrees C, the aucosa will undergo a co-analysis transition to form a pearleth (P)2, de-stressed annealing heating steel to a certain temperature below the Ac1 line, generally 500 to 600 degrees C, cold cooler after the process of coolingThe main purpose is to eliminate stress during welding, casting, forging and machining 3, re-crystallizing annealing chiller workpieceafter after a certain amount of cold plastic deformation, in the grain inside a large number of lattice distortion and dislocation, resulting in hardness, strength and plasticity reduction, that is, the phenomenon of process hardening, but also a large residual internal stress This makes it difficult to further plastic deformation If such steel is heated to a certain temperature above (less than Ac1, generally 600 to 700 degrees C), will re-core into a uniform grain, thus eliminating the phenomenon of processing hardening and residual stress, steel and restore the ability of plastic deformation This phenomenon is called recrystallization the heating the steel to the upper critical point (sub-common steel for Ac3, over-co-analysis steel for Accm) above the appropriate temperature, insulation for a certain period of time, and then cooled in the air process method called positive fire Among them: Accm line refers to the phase-change temperature line of the common analysis steel The purpose of is: 1) coolers improve the cutting performance of steels with low carbon content 2) When the requirements of carbon structure steel are not high, it can replace the modulation as heat treatment, and play the purpose of simplifying the process 3) Eliminate the mesh carburizing of the common analysis steel 4) Eliminate defects, refine grains, improve tissue, and prepare for heat treatment