AN EXPERIMENTAL COMPARISON BETWEEN TRADITIONAL AND DIE ASSISTED QUENCHING MANUFACTRURING PROCESSES AIDED BY MULTI-PHYSICAL MODELLING

Steel quenching is a milestone process that permits the achievement of required material performances, particularly in terms of hardness and mechanical resistance. On the other hand, it induces unavoidable changes of dimensions and shape of processed parts due to microstructure transformations and the rise of residual stresses. These variations are well known as distortions and mainly depend on the thermal gradients encountered through the cooling stage. The traditional Open Tank Oil Quenching process ensures the metallurgical phase transformations without strictly controlling the thermal behaviour of processed parts. In the last few decades the Die Assisted Oil Quenching process has been developed with the aim to reduce and control distortions of quenched parts. This process permits optimised metallurgical phase transformations with a reduction of the dimensional variations of steel parts. As a consequence, a reduction of allowances is typically expected due to a reduction about the need of remanufacturing operations (grinding). In present paper, a Design of Experiment has been realized by comparing both quenching processes and involving a number of combinations between materials and geometries obtaining the dimensional evolutions of the samples by means of a coordinate measuring machine. Furthermore, a multi-physical model of quenching process has been carried out through a layered physics approach to replicate experimental results.