Effects of alloying elements on microstructure and fracture properties of cast high speed steel rolls

The plasma surface alloying low-alloy high speed steel (HSS) is carried out in vacuum chamber where a source electrode (W-Mo) and a work piece are properly placed. By using the sputter of glow-discharge, under the common function of electric field and temperature field, ?????? the desired alloying elements (W- Mo) are sputtered from the source cathode, traveling toward the substrate. Subsequently the alloying elements deposit onto the surface of the substrate, forming alloy diffusion layer which the depth may vary from several micron to several hundreds micron. In the end a surface low-alloy HSS steel would be produced after ultra-saturation ion carbonization. The composition of the alloyed layer is equal or similar with it of low-alloy HSS. The carbonized layer, without coarse eutectic ledeburite structure, possesses high density of finely and dispersed alloy carbides with tungsten equivalent 10% above and a significant improvement in surface hardness and wear resistance. The principle of plasma surface alloying and its test results and commercial products application are introduced in this paper.

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Process Optimization and Properties of Laser Cladding High Vanadium High Speed Steel Coatings on Nodular Cast Iron

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.611 ◽

2013 ◽

Vol 712-715 ◽

pp. 611-614 ◽

Cited By ~ 6

Author(s):

Ni Jun Xu ◽

Jian Bin Lv ◽

Ting Sun ◽

Chang Sheng Liu

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Laser Cladding ◽

High Speed ◽

High Speed Steel ◽

Nodular Cast Iron ◽

Vanadium Content ◽

Treatment Technology ◽

Metallurgical Bonding ◽

Steel Rolls

As withstanding very high loads, thermal cycling leading to thermal fatigue, and severe environmental in the steel industry, rolls with long service life are specially required. High speed steel with high vanadium content is a newly-developed wear-resistance material that has been studied and used in some countries for making steel rolls. As a surface treatment technology, laser cladding can fabricate coating to improve the wear resistance of substrate. In this paper, the substrates for laser cladding were nodular cast iron rolls, Nd: YAG solid pulsed laser was used to explore the feasibility of preparation high vanadium high speed steel (HVHSS) coatings. The Nd: YAG laser cladding results that the coated layers combined metallurgically with the substrate with a lot of microcracks. The average microhardness up to 650 HV is more than 2 times as high as that of the substrate. After laser remelting, a fully dense and crack free HVHHS coating with an excellent metallurgical bonding was deposited. The presence of VC in the coating mainly improves the microhardness of coating up to about 650 HV.

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Loss of alloying elements in the melting of high-speed steel

Metallurgist ◽

10.1007/bf00739435 ◽

1970 ◽

Vol 14 (5) ◽

pp. 304-306

Author(s):

N. M. Chuiko ◽

M. I. Gasik ◽

N. T. Zaozernyl ◽

G. P. Parkhomenko

Keyword(s):

High Speed ◽

High Speed Steel ◽

Alloying Elements

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A Study of the Carbides in High-Speed Steel Rolls

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.3356 ◽

2010 ◽

Vol 638-642 ◽

pp. 3356-3361 ◽

Cited By ~ 2

Author(s):

Yi Kun Luan ◽

Nan Nan Song ◽

Xiu Hong Kang ◽

Dian Zhong Li

Keyword(s):

Heat Treatment ◽

Grain Boundaries ◽

High Speed ◽

Solidification Rate ◽

High Speed Steel ◽

Eutectic Carbides ◽

Complex Carbides ◽

Steel Rolls ◽

Alloy Concentration

Carbides in HSS roll were studied systematically. The results showed that there were two kinds of carbides in HSS roll, 1st and 2nd carbides. 1st eutectic carbides included the chrysanthemum-like MC mainly consisting of V and the plate-like M2C rich in Mo. 2nd carbides were complex carbides, concentrating Fe, Cr, Mo and V elements. The morphology, distribution and alloy concentration of the 1st eutectic carbides were studied using OM, SEM and EDS. During heat treatment, evolution of the 1st eutectic carbides was analyzed. It was found that the MC carbides had no change in morphology, components and distribution, while the M2C carbides decomposed to M6C and MC. In order to improve the properties of HSS, a method of increasing solidification rate was defined to refine the eutectic carbides. After refinement, the eutectic carbides distributed both along the grain boundaries and inside the grains.

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Features of technology for manufacturing cast toolbills from rapid-cutting steel R6M5

Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY) ◽

10.21122/1683-6065-2020-4-68-74 ◽

2020 ◽

pp. 68-74

Author(s):

F. I. Rudnitsky ◽

L. P. Dolgiy

Keyword(s):

Computer Simulation ◽

High Speed ◽

High Speed Steel ◽

Alloying Elements ◽

Steel R6m5 ◽

Gating System ◽

Cutting Steel ◽

Gear Shaping

The article presents the results of computer simulation of the crystallization of castings from high-speed steel R6M5, intended for the manufacture of cutters and gear shaping tools in the conditions of OJSC “Minsk Gear Plant”. The use of modeling made it possible to optimize the gating system, reduce this volume of the profitable part by 30–35 % and increase the yield of suitable casting, which made it possible to reduce the consumption of expensive alloying elements introduced into the melt to compensate for burnout during melting and casting.

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