SU1463793A1 - High-speed steel - Google Patents

Abstract

The invention relates to metallurgy, in particular to high speed steel, intended for the manufacture of cast metal-cutting tools. The purpose of the invention is to reduce the hardness in the annealed condition and to build toughness while maintaining the hardness, heat resistance and wear resistance of steel. The steel additionally contains niobium in the following ratio of components, wt.%: Carbon 0.82-0.89, chromium 3.7-4.3, tungsten 6.4-6.9, molybdenum 5, From-5.4,. vanadium 1.8-2, O, silicon 0.4-0.5 ,. manganese 0.3–0.4, cobalt 4.5–4.9, nickel 0.2–0.4, aln 4– 0.42–0.90, niobium 0.05–0.15, iron the rest. The use of steel will increase the service life of the tool. 2 tab. but

Description

one

The invention relates to metallurgy, in particular to high-speed steel, which can be used to make a cast metal-cutting tool. The aim of the invention is to reduce the hardness in the annealed condition and increase the toughness while maintaining the hardness, heat resistance and wear resistance of steel.

Steel is smelted in a high-temperature resistance furnace with graph. with a heater in apundum crucibles. Samples are cast in preheated graphite chills. After knockout, they are subjected to isothermal annealing and dp mechanical tests are prepared. The heat treatment of these samples is carried out in the following mode: heating for quenching to 1230 ° C, oh-.

salt bathing up to 250 ° C, holding at this temperature and further cooling in the salt bath up to 250 ° C, holding at this temperature and further cooling in air, tempering at 560 ° C for. 1 h, three times. Samples of known steel are subjected to a similar heat treatment.

The chemical composition, the results of the study of the properties of the proposed and known steels are presented in Table. 1-2.

The toughness test was carried out on 10.10 "55 mm standard uncut samples with a distance of 40 mm between the supports. Wear resistance is determined by the weight loss of the samples as a result of abrasion.

4ik

Od

00

with

under dry sliding friction of a hard-alloy disk under a load of 200 N

Heat resistance is estimated by measuring the hardness of the samples after additional heating to 620 ° C and a four-hour test at this temperature.

The impact viscosity of the proposed steel is 1.5 times higher than that of the known steel with practically equal hardness and wear resistance.

The hardness of the proposed steel is lower in comparison with: known in the annealed condition, facilitates machining by cutting when making a tool from it.

Formula

image

High-speed steel containing carbon, chromium, tungsten, molybdenum.

vanadium, silicon, manganese, cobalt, nickel, aluminum, iron, characterized in that

g decreasing the hardness in the annealed sos — that is, the impact strength and toughness while maintaining hardness, heat resistance, and wear resistance; it additionally contains niobium at the following ratio of components, wt /:

five

0

Carbon

Chromium

Tungsten

Molybdenum

Vanadium

Silicon

Manganese

Cobalt

Nickel

Aluminum

Niobium

Iron

0.82-0.89

3.7-4.3

6.4-6.9

5.0-5.4

1.8-2.0

0.4-0.5

0.3-0.4

4.5-4.9.

0.2-0.4 0.42-0.90 0.05-0.15 Else

Table i

Offered I

2

3

Known

four

0,823,76,45,01,800,400,304.50,200,420,05-Ostal XQ i o f -, 220,690,12-

0,894,36,9-5,42,000,500,404,901400), 844,16,425,32,01,050,284,70,320,25-0,30; Contains in the form of impurities sulfur and phosphorus in the amount of 0,01-0,02 wt.% Each. Table 2

Claims (1)

Claim High-speed steel containing carbon, chromium, tungsten, molybdenum, vanadium, silicon, manganese, cobalt, nickel, aluminum, iron, characterized in that, in order to reduce the hardness in the annealed state and increase the toughness while maintaining hardness, heat resistance and wear resistance , it additionally contains niobium in the following ratio of components, wt.%: Carbon 0.82-0.89 Chromium 3.7-4.3 Tungsten 6.4-6.9 Molybdenum 5.0-5.4 fifteen Vanadium 1.8-2.0 Silicon 0.4-0.5 Manganese 0.3-0.4 Cobalt 4.5-4.9. Nickel 0.2-0.4 20 Aluminum 0.42-0.90 Niobium 0.05-0.15 Iron Rest Table ί Melting Content of elements, wt.% steel FROM SG AND Mo V Si Mp With Hi Al Nb IN Fe Offers. gay 1 0.82 3,7 6.4 5,0 1.80 0.40 0.30 4,5 0.20 0.42 0.05 0 steel 2 0.86 4.1 6.5 5,4 1.95 0.47 0.34 4.4 0.22 0.69 0.12 New "W ¹¹ - · 3 0.89 4.3 6.9- 5,4 2.00 0.50 0.40 4.9 0.40 0.90 0.15 - Famous 4 0.84 4.1 6.42 5.3 2.0 1.05 0.28 4.7 0.32 0.25 - 0.30 __ * Contains sulfur and phosphorus in the form of impurities in an amount of 0.01-0.02 wt.% Each table 2 Float If- To the person Tempe Micro- Tver Tver Hit-, Heat- ka honest state ratrata tv er Dost Dost naya wait- sta- in dumb transforming Dost HB HRC elm- bone whether grains tally puppies matrix (after bone, HRC on the . human ° C qs, GPa otzhi- kJ / m ^2, 620 ° C 1 mm in to ha) 4 h PCS. opinion on 1 mm ⁴ , PCS. Wear resistance, mg / h 1 14.5 58 840 10.40 240 66 140 61 54 2 ’ 14.5 64 845 10.55 230 66 140 62 54 3 15.0 63 845 11.00 240 66. 120 62 56 4 10.0 131 860 8.20 320 66.5 65 62.5 51