Next Article in Journal
Method of Preparation for High-Purity Nanocrystalline Anhydrous Cesium Perrhenate
Next Article in Special Issue
Corrosion Behavior of API X100 Steel Material in a Hydrogen Sulfide Environment
Previous Article in Journal
Experimental and Numerical Simulation Investigation on Laser Flexible Shock Micro-Bulging
Previous Article in Special Issue
Assessment of the Residual Life of Steam Pipeline Material beyond the Computational Working Time
Article Menu
Issue 3 (March) cover image

Export Article

Open AccessArticle
Metals 2017, 7(3), 94; doi:10.3390/met7030094

Effect of Heat Treatment on the Microstructure and Mechanical Properties of Nitrogen-Alloyed High-Mn Austenitic Hot Work Die Steel

State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing (USTB), Beijing 100083, China
*
Author to whom correspondence should be addressed.
Academic Editor: Robert Tuttle
Received: 27 January 2017 / Revised: 9 March 2017 / Accepted: 10 March 2017 / Published: 14 March 2017
(This article belongs to the Special Issue Alloy Steels)
View Full-Text   |   Download PDF [9335 KB, uploaded 15 March 2017]   |  

Abstract

In view of the requirements for mechanical properties and service life above 650 °C, a high-Mn austenitic hot work die steel, instead of traditional martensitic hot work die steel such as H13, was developed in the present study. The effect of heat treatment on the microstructure and mechanical properties of the newly developed work die steel was studied. The results show that the microstructure of the high-Mn as-cast electroslag remelting (ESR) ingot is composed of γ-Fe, V(C,N), and Mo2C. V(C,N) is an irregular multilateral strip or slice shape with severe angles. Most eutectic Mo2C carbides are lamellar fish-skeleton-like, except for a few that are rod-shaped. With increasing solid solution time and temperature, the increased hardness caused by solid solution strengthening exceeds the effect of decreased hardness caused by grain size growth, but this trend is reversed later. As a result, the hardness of specimens after various solid solution heat treatments increases first and then decreases. The optimal combination of hardness and austenitic grain size can be obtained by soaking for 2 h at 1170 °C. The maximum Rockwell hardness (HRC) is 47.24 HRC, and the corresponding austenite average grain size is 58.4 μm. When the solid solution time is 3 h at 1230 °C, bimodality presented in the histogram of the austenite grain size as a result of further progress in secondary recrystallization. Compared with the single-stage aging, the maximum impact energy of the specimen after two-stage aging heat treatment was reached at 16.2 J and increased by 29.6%, while the hardness decreased by 1–2 HRC. After two-stage aging heat treatment, the hardness of steel reached the requirements of superior grade H13, and the maximum impact energy was 19.6% higher than that of superior grade H13, as specified in NADCA#207-2003. View Full-Text
Keywords: austenite hot work die steel; heat treatment; microstructure; mechanical properties; nitrogen austenite hot work die steel; heat treatment; microstructure; mechanical properties; nitrogen
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Zhang, Y.; Li, J.; Shi, C.-B.; Qi, Y.-F.; Zhu, Q.-T. Effect of Heat Treatment on the Microstructure and Mechanical Properties of Nitrogen-Alloyed High-Mn Austenitic Hot Work Die Steel. Metals 2017, 7, 94.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Metals EISSN 2075-4701 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top