Influence of Selective Laser Melting Technology Process Parameters on Porosity and Hardness of AISI H13 Tool Steel: Statistical Approach

The correct setting of laser beam parameters and scanning strategy for Selective Laser Melting (SLM) technology is a demanding process. Usually, numerous experimental procedures must be taken before the final strategy can be applied. The presented work deals with SLM technology and the impact of its technological parameters on the porosity and hardness of AISI H13 tool steel. In this study, we attempted to map the dependency of porosity and hardness of the tested tool steel on a broad spectrum of scanning speed–-laser power combinations. Cubic samples were fabricated under parameters defined by full factorial DOE, and metallurgic specimens were prepared for measurement of the two studied quantities. The gathered data were finally analyzed, and phenomenological models were proposed. Analysis of the data revealed a minimal energy density of 100.3 J/mm3 was needed to obtain a dense structure with a satisfactory hardness level. Apart from this, the model may be used for approximation of non-tested combinations of input parameters.

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Selective laser melting of Fe-Ni-Cr layer on AISI H13 tool steel

Transactions of Nonferrous Metals Society of China ◽

10.1016/s1003-6326(08)60378-7 ◽

2009 ◽

Vol 19 (4) ◽

pp. 921-924 ◽

Cited By ~ 35

Author(s):

Byeong-Don JOO ◽

Jeong-Hwan JANG ◽

Jae-Ho LEE ◽

Young-Myung SON ◽

Young-Hoon MOON

Keyword(s):

Selective Laser Melting ◽

Tool Steel ◽

Laser Melting ◽

H13 Tool Steel ◽

Aisi H13 ◽

Aisi H13 Tool Steel

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Process-Structure-Property Relationships of AISI H13 Tool Steel Processed with Selective Laser Melting

Materials ◽

10.3390/ma12142284 ◽

2019 ◽

Vol 12 (14) ◽

pp. 2284 ◽

Cited By ~ 12

Author(s):

Morteza Narvan ◽

Kassim S. Al-Rubaie ◽

Mohamed Elbestawi

Keyword(s):

Relative Density ◽

Selective Laser Melting ◽

Tool Steel ◽

Crack Formation ◽

Dendritic Structure ◽

Laser Melting ◽

Scanning Strategy ◽

H13 Tool Steel ◽

Aisi H13 ◽

Aisi H13 Tool Steel

Due to a good combination of high hardness, wear resistance, toughness, resistance to high operating temperatures, and fairly low material cost, AISI H13 tool steel is commonly used in the manufacture of injection molds. Additive manufacturing (AM) such as selective laser melting (SLM), due to the layer-wise nature of the process, offers substantial geometric design freedom in comparison with conventional subtractive manufacturing methods, thereby enabling a construction of complex near-net shape parts with internal cavities like conformal cooling channels. The quality of SLM-manufactured parts mainly depends on the part geometry, build orientation and scanning strategy, and processing parameters. In this study, samples of H13 tool steel with a size of 10 × 10 × 15 mm3 were SLM-manufactured using a laser power of 100, 200, and 300 W; scanning speed of 200, 400, 600, 800, 1000, and 1200 mm/s; and hatch spacing of 80 and 120 µm. A constant layer thickness of 40 µm, 67° scanning rotation between subsequent layers, and a stripe scanning strategy were maintained during the process. The samples were built considering a preheating of 200 °C. The relative density, surface roughness, crack formation, microstructure, and hardness were evaluated. The relative density is shown to increase with increasing the volumetric energy density up to a value of about 60 J/mm3 and then no significant increase can be pointed out; the maximum relative density of 99.7% was obtained. A preheating of 200 °C generally aids to increase the relative density and eliminate the crack formation. The microstructure of built samples shows fine equiaxed cellular-dendritic structure with martensite and some retained austenite. The microhardness of the as-built samples was found to vary from 650 to 689 HV 0.2, which is comparable to a conventionally produced H13 tool steel.

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Impact Testing of H13 Tool Steel Processed with Use of Selective Laser Melting Technology

Materials Science Forum ◽

10.4028/www.scientific.net/msf.919.43 ◽

2018 ◽

Vol 919 ◽

pp. 43-51 ◽

Cited By ~ 3

Author(s):

Michal Ackermann ◽

Jiří Šafka ◽

Lukáš Voleský ◽

Jiří Bobek ◽

Jitendra Reddy Kondapally

Keyword(s):

Selective Laser Melting ◽

Tool Steel ◽

Mechanical Tests ◽

Impact Testing ◽

Pressure Casting ◽

Laser Melting ◽

Impact Properties ◽

H13 Tool Steel ◽

Processed Material ◽

Aisi H13

This paper deals with experimental determination of toughness, hardness and impact properties of AISI H13 (DIN 1.2344) tool steel which was manufactured using Selective Laser Melting (SLM) technology. The H13 is a chromium-based tool steel which is primarily used for hot working applications such as pressure casting moulds for automotive industry. Evaluation of toughness and impact properties are vital for reliable use of SLM-processed material, especially in the case of highly loaded structures. Mechanical tests were carried out on printed specimens, subjected to thermal treatment and proper data were evaluated. For better understanding of differences between conventionally produced and SLM-processed material, same mechanical tests were done even for hot-rolled H13 tool steel. SLM-printed material shows more brittle behaviour than conventionally made material. This is most probably caused by combination of H13 thermal properties and fast melting and solidification due to SLM processing.

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