Wear-resisting alloy steel with high boron, high chrome and low carbon and preparation method thereof

Abstract

The invention discloses a wear-resisting alloy steel with high boron, high chrome and low carbon and a preparation method thereof, which comprises the following chemical constituents in weight percent: 0.1-0.5% of C, 3-26% of Cr, 0.5-1.2% of Si, 0.5-1.5% of Mn, 0.3-2.8% of B, 0.3-2.6% of Cu, 0.2-0.6% of Ti, 0.02-0.15% of Ca, 0.03-0.25% of Ce, 0.02-0.18% of N, 0.05-0.3% of Nb, 0.04-0.09% of Al, 0.02-0.15% of Mg, 0.04-0.13% of K, less than 0.03% of S, less than 0.04% of P and the balance Fe and unavoidable impurity elements. The method comprises the following steps: melting steel scrap and chromium iron in an electric furnace; adding copper plates, ferrosilicon, ferromanganese into the melted steel scrap and chromium iron, heating the melt to 1560-1620 DEG C after the constituents are adjusted to be qualified in stokehold; adding calcium-silicon alloy and aluminium deoxidation into the melt; and then adding ferrotitanium and ferroboron in sequence, melting and discharging; roasting the compound inoculant composed of granular rare earth magnesium alloy with the diameter being less than 12mm and cerium metal, Si3N4, VN, Nb and K; placing the roasted compound inoculant at the bottom ofa steel ladle; carrying out modification and inoculation processes on the smelted liquid steel by pour-over method in the steel ladle, wherein, the pouring temperature of the liquid steel is 1400-1450DEG C; heating castings to 920-1150 DEG C and preserving heat for 2-4 hours; and air cooling the castings to room temperature to obtain the alloy steel in the invention. The alloy steel of the invention has the advantages of high strength, rigidity and toughness, good thermal fatigue resistance property, wear resistance, and low manufacture cost.

Description

Technical field [0001] The invention belongs to the technical field of steel materials, and relates to a casting wear-resistant mold steel and a preparation method thereof, in particular to a high-boron, high-chromium, low-carbon wear-resistant alloy steel and a manufacturing method thereof. Background technique [0002] The development of modern science and technology has higher and higher requirements for materials. Abrasion is a common occurrence in mining, metallurgy, machinery, electricity, coal, petroleum, building materials, transportation and other industrial sectors and has become an important cause of equipment damage or material failure and energy consumption. It is also one of the three main failure modes of mechanical parts. The research and development of a new generation of wear-resistant materials to reduce metal wear is of great significance to the national economy. At present, the widely used metal wear-resistant materials mainly include alloy steel and cast iro...

AI Technical Summary

Problems solved by technology

However, due to the low boron content (0.15-0.3%) of this boron-containing high-chromium wear-resistant cast iron, the boride content in the alloy is small, so that its wear resistance is still low; High (2.5~3.5%C), which makes its toughness low, and its safety performance is poor under heavy load and large impact wear conditions; due to the use of more alloys for modification treatment, the modification process is complicated and the cost increases

[0008] Although boron-containing high-chromium cast iron has good wear resistance, the addition of boron will increase the number of carbides and borides, which will reduce the toughness of high-chromium cast iron alloys. If you want to improve toughness, you need to add molybdenum, nickel, etc. Expensive alloying elements increase production costs

Therefore, although boron-containing high-chromium cast iron has been studied at home and abroad, it has not been widely promoted and applied because its strength and toughness have not been resolved.