Effect of Nitrogen and Niobium on the Structure and Secondary Hardening of Super Hard High Speed Tool Steel

Halfa, Hossam; Eissa, Mamdouh; El-Fawakhry, Kamal; Mattar, Taha

doi:10.1002/srin.201100094

Cited by 16 publications

(10 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[12][13][14][15] Although there are relatively few studies on the application of N in HSS, it has been gradually recognized that adding N has a positive effect in improving the microstructure and property of HSS. Mattar et al 3) and Halfa et al 16) reported that adding N (0.115-0.145 wt.%) to M41 HSS could refine the as-cast microstructure, promote the breaking up of eutectic network, reduce the amount and size of eutectic carbides, and meanwhile increase the secondary hardening peak and wear resistance. Cieśla et al 17) demonstrated that introducing N to HS-6-5-2 HSS (0.019-0.057 wt.%) could refine the microstructure and increase the dispersion degree of primary and secondary carbides, and thereby significantly increase the resistance to brittle cracking (K IC ).…”

Section: Introductionmentioning

confidence: 99%

Effect of High Nitrogen Addition on Microstructure and Mechanical Properties of As-cast M42 High Speed Steel

Jiao

Feng

et al. 2020

ISIJ Int.

View full text Add to dashboard Cite

This study systematically investigated the influence of high nitrogen (N) addition (0.205 wt.%) on microstructure and mechanical properties of as-cast M42 high speed steel. The results demonstrate that the conventional and high-nitrogen M42 cast ingots are mainly composed of martensite, retained austenite and various precipitates (M 2 C, M 6 C as well as MC in M42 cast ingot or M(C, N) in M42N cast ingot). The addition of N could increase the retained austenite content, trigger the transformation of MC to M(C, N), favor the formation of M 2 C at the expense of M 6 C, and improve the distribution uniformity of M 6 C at the macroscopic scale. Moreover, the addition of N could lead to the reduction of the secondary dendrite arm spacing as well as the decrease of the thickness and area fraction of eutectic carbides, and improve the distribution uniformity of eutectic carbides at the microscopic scale. The M(C, N) particles form directly from the liquid phase prior to the formation of primary austenite, which could act as the heterogeneous nuclei of primary austenite and thus promote the refinement of the as-cast microstructure. The addition of N slightly decreases the macro-hardness and ultimate compression strength of the cast ingot but increases its ductility, which could be ascribed to the increase of retained austenite content and the reduction in the amount of eutectic carbides. Therefore, high N addition can significantly improve the as-cast microstructure of M42 high speed steel, which is promising for the further enhancement of the mechanical property and service life of the final product.KEY WORDS: M42 high speed steel; pressurized metallurgy; nitrogen; as-cast microstructure; precipitates; mechanical property. N i J J J J J D

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of High Nitrogen Addition on Microstructure and Mechanical Properties of As-cast M42 High Speed Steel

Jiao

Feng

et al. 2020

ISIJ Int.

View full text Add to dashboard Cite

show abstract

“…Terefore, an enormous amount of time and work would be required to perform its experimental investigation. Terefore, considering these purposes for investigating the previous multicomponent system, many researchers have successfully utilized the CALPHAD method for phase equilibrium estimation [23,[32][33][34][35][36][37].…”

Section: Resultsmentioning

confidence: 99%

Study on the Microstructure of Vanadium-Modified Tungsten High-Speed Steel-Coded SAE-AISI T1 Steel

Halfa

Seikh

Abdo

et al. 2022

Advances in Materials Science and Engineering

Self Cite

View full text Add to dashboard Cite

The essential goal of this research is to evaluate the modification process on phase transformation, matrix chemical composition, and precipitated carbide types for modified SAE-AISI T1 steel and their effects on the hardness values after optimum heat treatment conditions. This research adopts the alloying design strategy to enhance one of the most important tools steel coded SAE-AISI T1 (T12001). Therefore, two alloying enhancement processes took place through partial or total tungsten replacement. Investigated steel was modified first through the addition of vanadium and then through the addition of vanadium and carbon. Substitute 5 wt modified SAE-AISI T1 steel. % tungsten with 1 wt. % vanadium, in addition to carbon content, varied from 0 to 1 wt. %. Therefore, to fulfill the goals of this work, Thermo-Calc software was utilized to get the following: (i) thermodynamic equilibrium information, (ii) the expected microstructure, (iii) the constituent volume fraction, and (iv) carbide chemical composition. The chemical composition of the expected phases was confirmed by scanning electron microscopy (SEM) equipped with energy-dispersive X-ray (EDX). In addition, volume fractions of different constituents were estimated by using Thermo-Calc software and authenticated by the imaging analysis process. The experimental findings for the variations in the chemical composition of the matrix and eutectic carbides precipitated, e.g., MC and M6C carbides, agree well with the calculated findings. Tungsten replacement by vanadium with and without extra carbon at traditional SAE-AISI T1 steel encourages MC carbide formation instead of M6C, M23C6, and M7C3 carbides. MC carbide precipitated in vanadium with extra carbon-modified steel contains more carbon, chromium, and tungsten but less vanadium compared with vanadium-modified steel. Vanadium with extra carbon-modified steel precipitated more M6C carbide and gamma-austenite. Hardness measurements emphasized that modified steel is a promising material for its use as a tooling material with low tungsten content and, in turn, produces cutting-tool materials with economical cost.

show abstract

“…MC, M6C, M2C, and M7C3 carbides precipitated from liquid steel directly in non-equilibrium condition; reactions, phase transformation starting time, and solid fraction are listed in Table 4. However, M6C and M7C3 carbides cannot be found in microstructure, which may be attributed to rapid solidification resulting to precipitation of carbides from austenite phase scarcely [22]. Thus, the microstructure consists of austenite, eutectic Mo2C, and VC carbides.…”

Section: Phases Formation Calculated With Thermo-calc Softwarementioning

confidence: 99%

Precipitation Behaviors of Carbides in High Speed Steel during ESR and Heat Treatment

Liu

Liang

et al. 2021

Metals

View full text Add to dashboard Cite

The microstructure and carbides evolution of high-speed steel after electroslag remelting and solution treatment were studied. The thermodynamic precipitation mechanism of carbides in solid phase was discussed and the characteristic parameters of carbides in different processes were also investigated. The results show that there were large lamellar and fibrous Mo2C and a small amount of VC in the ESR ingot. Mo2C are metastable carbides, which can be decomposed into VC and Fe2Mo4C during the solution treatment. The average diameter of the carbides is reduced to 1.28 μm and the space distance is reduced to 3.23 μm after forging and hot rolling, which means carbides are completely spheroidal and dispersed in matrix.

show abstract

Effect of Nitrogen and Niobium on the Structure and Secondary Hardening of Super Hard High Speed Tool Steel

Cited by 16 publications

References 8 publications

Effect of High Nitrogen Addition on Microstructure and Mechanical Properties of As-cast M42 High Speed Steel

Effect of High Nitrogen Addition on Microstructure and Mechanical Properties of As-cast M42 High Speed Steel

Study on the Microstructure of Vanadium-Modified Tungsten High-Speed Steel-Coded SAE-AISI T1 Steel

Precipitation Behaviors of Carbides in High Speed Steel during ESR and Heat Treatment

Contact Info

Product

Resources

About