Übersetzung für "Austenitization" in Deutsch

Austenitization may be performed over a period of 10 to 40 minutes.

The tempering treatment itself consists, as is known, of heating to austenitization temperature, quenching and annealing.

While the austenitization taking place during the temper-hardening as a special homogenization treatment, the latter is performed by the heating in the rolling mill furnace, as well as by the rolling process itself, during the production of steel tension members according to the invention.

A main feature for the success is in particular the combination of the austenitization temperature of about 950° to 1050° C., which lies above respective temperatures in known heat treatments, with the heating of the rail head portion to 600° to 650° C. after finishing the pearlite transformation.

It was found that at the slightly raised austenitization temperature of 850° C. and higher, and also with a holding time of at least 10 minutes at that temperature, the graphite is dissolved, therefore making possible the good hardenability of the steel.

The quenching after austenitization in the heat treatment of steels represents an important step in the termination of the process.

The authors consider the usefulness of simultaneous addi­tions of molybdenum or vanadium which would make it possible to disperse the carbides during the austenitization process.

For reasons of hardenability, unalloyed and alloyed heat-treated steels require a coarse austenite grain (ASTM number 6 or smaller No.) during austenitization prior to hardening.

If such steels were to be completely killed with aluminium, the aluminium nitrides formed in the course of austenitization or already present would cause grain refining by nucleation or by impeding the growth of the austenite grain.

In dependence on the aluminium or nitrogen contents, with the usual austenitization temperature of about 800° to 860° C. a fine austenite grain would be formed in these steels and heavily reduce their hardenability.

With steels having aluminum contents of more than 0.015%, such as are present with full aluminium killing, austenitization temperatures of the order of magnitude of between 950° and 1050° C. would be required to obtain a coarse-grained austenite.

Such austenitization temperatures cannot be considered, for reasons of energy costs, technical plant limitations and relatively heavy scaling.

Hitherto the coarse austenite grain has been obtained by limiting the maximum aluminium content to 0.005% with ordinary and 0.010% with elevated austenitization temperatures.

Here, a blank or a semifinished part is heated to austenitization temperature and subsequently placed in a shaping tool with a press.

Here, regions of the semifinished part that have to transmit deep drawing forces during the shaping are cooled in a dosed manner after heating to a temperature above austenitization temperature and prior to contact of the appropriate regions with the shaping tool without reaching in the regions the cooling rate necessary for hardening.

The method according to claim 3, wherein austenitization of the shaped tool occurs at a temperature of 1200° C. with a dwell period thereat of maximum 15 minutes.

An austenitization of the material at a temperature of below 1210° C. and at least one tempering of the hardened steel in the temperature range of 500° C. to 600° C. are advantageous production parameters.

Before the heat treatment, the coil or the strip are brought to a predetermined temperature which, as a rule (for steel), corresponds to the austenitization temperature.