SU1326627A1 - Die steel - Google Patents

Abstract

The invention relates to ferrous metallurgy, in particular to the composition of die steel, and makes it possible to increase the heat resistance and wear resistance of the die tool. The purpose of the invention is to increase the wear resistance and heat resistance of steel. This is achieved by the fact that steel contains components in the following ratio, wt.%: Carbon 0.4-0.6; silicon 0.15-0.35; manganese 0.5-0.8; aluminum 1.0-1.7; chromium 0.8-2.5; vanadium 0.07-0.60; molybdenum 0,2-0,8; nickel 1.4-1.8; iron the rest, provided that the ratio of Mn + Ni / Al 1,5-1,9. The use of steel will increase the resistance of the stamps by 30 - 65%. 2 tab.

Description

The invention relates to metallurgy, in particular, to the composition of tool steel for the manufacture of hot forming dies.

The purpose of the invention is to increase the wear resistance and heat resistance of steel.

An increase in heat resistance and wear resistance is achieved by increasing the aluminum content by increasing the temperature of critical points of steel (Ac, and Ac,) and the recrystallization temperature.

The greatest increase in die resistance is observed, provided that the ratio

Mp + Ni,, ,, 1.5-1.9.

When the content of aluminum in steel is less than 1.0 wt.%, Its effect on the critical points and the temperature of the onset of recrystallization is practically not observed, as a result of which the durability is minimal.

The content in the steel is more than 1.7 wt.%

, Mp + Ni. . aluminum (when - 1.5) also leads to a decrease in resistance, although the recrystallization temperature, the critical points of steel and heat resistance increase. This is due to a decrease in the mechanical characteristics of the steel (strength and, in particular, its ductility and toughness).

Table 1 shows the chemical composition of the experimental melts from which samples were prepared for mechanical tests and inserts for precast dies on a detail of the Moskvich car stand (melts 2-4 are proposed steel; melting 6 is known steel; melts 1 and 3 have the contents of components beyond the proposed limits).

The cooling rates of the specimens for testing, the mechanical properties during quenching, corresponded to the cooling rates of the central part of the die cube 400x400x400 mm in size in oil.

Heat treatment mode, results. Tests of samples and durability of inserts of dies from known and proposed steels are presented in Table 2 (hardening and tempering temperatures 920 and, respectively).

The mechanical and operational properties of the proposed steel are of the optimal chemical composition, when corresponding to Mn + Ni

 BUT

Claims (1)

higher than that of known steel. The durability of stamps from the proposed steel is increased by 30-65%. Invention Formula Die-cutting steel containing carbon, genus, silicon, manganese, aluminum, chromium, nickel, vanadium, molybdenum, iron, is different; and with the fact that, in order to increase wear resistance and heat resistance, it contains components in the following ratio,, wt.%: wearing  1.5-1.9, meaning5 0 . Carbon Silicon Manganese Aluminum Chrome Molybdenum Nickel Vanadium Iron 0.40-0.60 0.15-0.35 0.5-0.8 1.0-1.7 0.8-2.5 0.20-0.80 1.4-1.8 0.07-0.60 Else Ni + Mp with the ratio tt  1.5 - 1.9. " but s h y " n  Heat resistance was determined in ° C from the limiting temperature of 4-hour tempering, after which the steel retains A5 unit hardness. Editor N.Kishtulinets Compiled by V. Brestrem Tehred L. Serdyukova Order 3250/22 Circulation 604 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, Projecto st., 4 Table 2 Proofreader L. Pilipenko