BS EN ISO 4885:2015 pdf download

3.166

quench-hardened layer

surface layer of a workpiece, hardened by quenching, the thickness of which is generally defined by the depthof quench hardening

3.167

quenching

operation which consists of cooling a workpiece more rapidly than in still air.Quenching include directquenching

NOTE 1 The use of a term specifying the cooling conditions is recommended,for example water quenching,oilquenching. step quenching, air-bllast quenching, etc.

NOTE 2 Quench hardening is hardening of a workpiece obtained, after austenitizing, by coling under conditions suchthat the austenite transforms more or less completely into martensite and possibly into bainite

NOTE3 For stainless steels quenching can be followed by solution annealing, see 3.186

3.168

quenching media

the media where the quenching is performed

NOTE Quenching media could be a liquid or a gas or a blend gas, e.g.: water, oil, nitrogen or argon

3.169

quenching temperature

temperafure at which quenching is initiatedcf.hardening temperature

3.170

recarburizing / carbon restoration

thermochemical treatment intended to restore the carbon content of the surtace layer, decarburized during anearlier treatment

3.171

recovery

heat treatment intended to cause at least partial recovery of the physical or mechanical properties of a cold-worked ferrous product without apparent modification of its structure

NOTE This treatment is carried out at a temperature below that of recrystallizing.3.172

recrystallizing

heat treatment intended to cause new grains to develop by nucleation and growth, in a work-hardened metal,without a change in phase

3.173

retained austenite

untransformed austenite remaining, at ambient temperature, after quench hardening

3.174

scale

layer which is formed during hot forming or heat treating in a non-protective atmosphere.NOTEUsually the scale is an oxide scale and is removed by blasting or pickling.