The quenching temperature is mainly determined according to the critical point of the wear resistant lining of high chromium cast iron.Subeutectoid steel is usually heated to 30~50℃above Ac3, while eutectoid steel and hypereutectoid steel are heated to 30~50℃above Ac1, and in some cases to 50 ~ 70℃above ^, as shown in the figure.If the quenching heating Temperature subeutectum ferro est inferior, quam quod de AC3, tum quod ferro non plene ausculorum in hoc tempore, et aliqua untransformed Ferrite existit, et ferritus manet in extinguendis, {et quod duritiam}} si non poterit, quod in hoc, quod in obressed {XII}}, si afficit, si in cæruleo, {{{}}, si in cæsibus, {{{}} Si enim est quod duritiam, ut non poterit, {}} {et afficit, si in exigere, {}} {et afficit, si in obruentiam {XII {}} si afficit, si in obressed {XII {}} si afficit, si in obruence {{}}, si afficit, si non poterit, ut exiguam} {{}}, si afficit, si in obruentiam, {{{}}, si afficit, si ad XII, {}}} si afficit, si in obruence {{}}, si afficit, si ad XII}}} subeutectoid steel is heated to the Ac3 temperature for quenching, the austenite grain will be significantly larger, thus damaging the properties after quenching.The eutectoid steel was heated above Ac1 at 30 ~ 50℃.After quenching, only a few residual austenite particles were found in vitro, and the structure was small carbide particles evenly distributed on the lamellar martensite matrix.Such tissues have high hardness, good wear resistance and relatively low brittleness.The quenching temperature of hypereutectoid steel cannot be lower than that of Ac1, because the steel has not been austenitized at this time.When heated to a temperature slightly higher than the temperature, the pearlite completely transforms into austenite and a small amount of cementite dissolves into austenite.The austenite grains were fine and the carbon mass fraction was higher than that of eutectoid.If the temperature continues to rise, the secondary cementite will continue to dissolve into austenite, resulting in the continuous growth of austenite grains and the increasing carbon concentration, which will lead to the increase of quenching deformation tendency, quenching microstructure Missiphrachs et fragtileness {{}}} simul, debitum ad altum austenite carbon contentus, moles RELICTUM Austenite auctus post extinxit, reducendo duritiam et gerunt residuam de gerunt, repugnant liner {}}}
Ergo extinguat calefactio temperatus hyperereuteoid ferro non idoneam esse nimis altius quam AC1 et calefacit ad temperatus plene auscum ACM vel superius etiam magis inconveniens
