High-Temperature Properties and Microstructural Stability of the AISI H13 Hot-Work Tool Steel Processed by Selective Las
- PDF / 5,286,224 Bytes
- 12 Pages / 593.972 x 792 pts Page_size
- 92 Downloads / 258 Views
NTRODUCTION
AISI H13 alloy is a hot-working tool steel that possesses ultra-high strength, favorable temper resistance, good thermal fatigue performance, and wear resistance at elevated temperature.[1,2] Hence, it has received considerable interests worldwide as one of the most attractive materials in hot-work tool operations, such as die casting, forging, and extrusion.[3,4] Thermal fatigue, erosion, and wear are the main causes of damage or failure of this material in service. Damaged areas of the parts are usually removed by CNC processing to create a new die surface, or are replaced with the entire component.[5] Spot or surface repair techniques, such as the laser cladding process is
MEI WANG, WEI LI, SHUAI LI, CHAO CAI, SHIFENG WEN, QINGSONG WEI, and YUSHENG SHI are with the State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, P.R. China. Contact e-mails: [email protected]; [email protected] YAN WU is with the Department of Industrial Engineering, University of Louisville, Louisville, KY 40292. FUYUAN YE and ZHIPING CHEN are with the Guangdong Kelon Mould Co., Ltd., Foshan 528303, P.R. China. Manuscript submitted February 1, 2018. Article published online November 2, 2018. METALLURGICAL AND MATERIALS TRANSACTIONS B
generally used for cost advantages.[4] These techniques can only repair the material after the parts fail, but they cannot improve the lifetime of the workpiece. Nowadays, the conformal structure with integrated cooling channels is commonly used in hot-nut tools and forging dies to improve the service life. Investigations on molds with the conformed channels have been reported in plastic injection mold applications, which is effective in reducing the cycle time and eliminating warpages.[6,7] In addition, the conventional wrought H13 parts exhibited inferior transverse properties and uneven hardness because of the coarse and inhomogeneous microstructures.[1] Therefore, alternative manufacturing techniques of AISI H13 alloy requires further development. Additive manufacturing (AM) has gained considerable popularity in recent years. The competitive advantages of AM are geometrical freedom, shortened design and product time, reduction in process steps, customization, and material flexibility.[8] SLM is a typical AM technology that can fabricate high-density parts with complex geometrical designs[8–10] and is capable of producing functional components from powders with mechanical properties comparable to that of traditional bulk material.[8,11] Customized medical parts and tooling inserts are good examples that reveal the application scope of this process.[12–14] Nowadays, some preliminary works have been carried out to illustrate the relationship
VOLUME 50B, FEBRUARY 2019—531
between microstructures and properties of H13 alloyed steel processed by SLM. Laakso et al. demonstrated the optimization of processing parameters of H13 tool steel by SLM.[15] The relative density of SLM-
Data Loading...
