SU908902A1 - Alloying composition - Google Patents

Description

(54) LIGATURE

This invention relates to ferrous metallurgy, in particular, to compositions of wagnadium-containing master alloys and alloys for deoxidation and alloying of steels and cast irons. Known vanadium containing C 11 ligatures for the deoxidation and alloying of steel and cast iron of the following composition, wt.%: Vanadium15-3 5 Silicon 1.5-2.5 Manganese 7-20 Chromium Up to 5 Carbon 0.5-1.5 Nitrogen 3-8 Aluminum Up to 3 IronOstal Tak The ligature, in spite of the high content of vanadium, does not allow the steel to be obtained & naught, and the increased mechanical properties of the products obtained from its steels .. Ligature 2 of the following composition is also known, wt.%: Vanadium Silicon Manganese 0.1-2.0 Carbon O., 0 0, O1 -O, 4 Iron Rest Dunn ligature due to low vanadium content It requires povppennogo flow that leads to a cooling of the metal, reducing its fluidity and povpiennomu Fukue nezapolnnemosti on forms, especially when casting thin-walled castings slslknoy configuration. Closest to the proposed technical essence and the achieved effect is a ligature H of the following composition, wt.%: Vanadium 15-50 Silicon 5-5 O Manganese 0.5-4.9 Chromium 0.5-3.0 Oleo, .-, 3.0 9 Titanium 0.05-5, O Nitrogen 0,01-0,2 Kapyshy0,005-5,0 Iron Other The disadvantage of this ligature lies in the low digestion of calysh and vanadium, as a result of which the level of the properties of the doped steel has not been high enough. The purpose of this process is to increase the degree of assimilation of vanadium and calcium from a ligature, to improve the strength, ductility, and cold resistance of steel. The goal is achieved by the fact that a ligature containing vanadium, silicon, manganese, chromium, carbon, titanium, nitrogen, calcium and iron, in fact, contains nickel with the following ratio of xalponents, wt.%: Vanadium 35-45 5-15 Silicon 0, 5-10.0 Manganese 0.5-3, O 0.5-3.0 Carbon 0.5-5.0 0.01-0.2 0, O5-1.5 Kalysh Nickel 0.5-9, 0 Iron Rest The narrowing of the concentration range of the main components of the master alloy, vanadium and silicon, stabilizes the degree of assimilation of vanadium by metal. Given the ratio of these components, the ingress of silicon into the ligature of silicon, as an element possessing a great means for oxygen, prevents vanadium from oxidation, increasing its degree of assimilation by the metal. An increase in silicon above 15% practically does not change the degree of assimilation of vanadium, since the decrease in the specific weight of league 24 tours as the concentration of silicon increases in it is very small. Increasing the manganese concentration in the ligature is related to the fact that it increases vanadium activity, increases the rate and completeness of its transition to the metal, reduces the melting point of the ligature, and, most importantly, helps to obtain low-melting inclusions based on manganese silicates in the doped metal. The chromium, carbon, titanium and nitrogen present in the same ratio together with vanadium in the process of dissolving the ligature, phase out nitrides and carbonitrides of vanadium, chromium and titanium, which at a given ratio of components provide the necessary mechanical and operational characteristics of the steel. The introduction of nickel into the ligature narrows the optimum range of calcium concentrations necessary to obtain a stable assimilation of its doped metals and a high level of its mechanical and operational characteristics. In addition, nickel introduced into the metal is assimilated by it, not forming non-metallic inclusions, practically by 1OO%. PRI me R. In 25O t of the open-hearth furnace, high-strength steel 18G2AF was heads out for the manufacture of welded metal structures. Steel deoxidation and alloying are used along with FeMn. and SiMii-known ligature. For the top of that part use the proposed ligature. The chemical composition of the ligatures is given in gabl, 1. The results of the steel alloying are given in table. 2. The data presented in the table show that the proposed ligature can significantly increase the absorption of vanadium and calcium and increase the properties of steel.

t- 88- 0.001- 45.6- 61,492, 1 0.05 48.4 66.5

94.6O, O151,, 0

94.6O.OZ51,569.1

96,40,0151,269,1

96.8, 0249,568,6

96.20, OZ50,468.8

96,00,0350,368,7

Claims (3)

1. USSR author's certificate No. 246861, cl. C 22 C 35/00, 1968. 2. USSR Author's Certificate No. 451779, class C 22 C 35 / OO, 197S. 3. USSR author's certificate: № 559992, cl. C 22 C 35 / OO, 1976.