Indirect selective laser sintering of metal parts with overhung features

Purpose Metal green parts fabricated by indirect selective laser sintering (SLS) have lower mechanical properties, and thus, they cannot satisfy practical application. To enhance their performance, two polymer resins were compounded as a modified material to infiltrate into the metal parts by SLS. Design/methodology/approach The viscosity and glass-transition temperature were tested by a viscometer and differential scanning calorimetry, respectively. The microstructure and morphology of the interface of parts by polymer resin infiltrated were observed to be using scanning electron microscopy. The tensile strength of sample parts was tested, too. The temperature tolerances of two mass ratio polymer materials were tested and compared by thermo-gravimetric analysis (TGA). Findings Compared to those without being polymer material infiltrated, the results of test showed that the tensile strength of the metallic parts is enhanced obviously, about four times. In addition, the analysis of TGA showed that the resin of mass ratio of 2:1 can be endured up to 200° and can be used as infiltrating materials for metal parts. Originality/value Therefore, plastic injection mold and function part can be manufactured by this method.

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Finite Element Simulation of Combined Forming of Selective Laser Sintering and Cold Isostatic Pressing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.26-28.60 ◽

2010 ◽

Vol 26-28 ◽

pp. 60-66

Author(s):

Yan Ying Du ◽

Yu Sheng Shi ◽

Qing Song Wei

Keyword(s):

Finite Element ◽

Metal Powder ◽

Selective Laser Sintering ◽

Good Method ◽

Laser Sintering ◽

Cold Isostatic Pressing ◽

High Porosity ◽

Isostatic Pressing ◽

Metal Parts ◽

Short Time

Selective Laser Sintering could manufacture high complex metal parts in short time but with high porosity and low strength. The components from Cold Isostatic Pressing have excellent performance with uniform organizational structure, high size precision, and high density. It, however, could not form high complex parts because of the difficulties of bag manufacture. So it will be a good method to combine Selective Laser Sintering and Cold Isostatic Pressing to make complicated metal parts. In this paper, the specimens of stainless steel were made by the combined Selective Laser Sintering and Cold Isostatic Pressing forming route. And the simulation of Cold Isostatic Pressing was carried out by finite element method and Drucker-Prager-Cap constitutive model in ABAQUS/Explicit computer program. The property of metal powder was measured by experiments. The effects of bag on Cold Isostatic Pressing have been discussed. It is different from the Cold Isostatic Pressing of metal powder that the bag has little influence on both shape and size of the specimen. The results of simulation show a good agreement between the experimental results and the calculated results. The simulation can give a useful direction to dimension and shape designs of the combined forming of Selective Laser Sintering and Cold Isostatic Pressing.

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Manufacturing AISI304 metal parts by indirect selective laser sintering combined with isostatic pressing

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-007-1295-2 ◽

2007 ◽

Vol 39 (11-12) ◽

pp. 1157-1163 ◽

Cited By ~ 3

Author(s):

Z. L. Lu ◽

Y. S. Shi ◽

J. H. Liu ◽

Y. Chen ◽

S. H. Huang

Keyword(s):

Selective Laser Sintering ◽

Laser Sintering ◽

Isostatic Pressing ◽

Metal Parts

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A novel microscale selective laser sintering (μ-SLS) process for the fabrication of microelectronic parts

Microsystems & Nanoengineering ◽

10.1038/s41378-019-0116-8 ◽

2019 ◽

Vol 5 (1) ◽

Cited By ~ 6

Author(s):

Nilabh K. Roy ◽

Dipankar Behera ◽

Obehi G. Dibua ◽

Chee S. Foong ◽

Michael A. Cullinan

Keyword(s):

Additive Manufacturing ◽

New Technology ◽

Selective Laser Sintering ◽

Three Dimensional ◽

Laser Sintering ◽

Metal Nanoparticle ◽

Metal Parts ◽

Nanoparticle Layer ◽

Slot Die ◽

Commercial Applications

AbstractOne of the biggest challenges in microscale additive manufacturing is the production of three-dimensional, microscale metal parts with a high enough throughput to be relevant for commercial applications. This paper presents a new microscale additive manufacturing process called microscale selective laser sintering (μ-SLS) that can produce true 3D metal parts with sub-5 μm resolution and a throughput of greater than 60 mm3/hour. In μ-SLS, a layer of metal nanoparticle ink is first coated onto a substrate using a slot die coating system. The ink is then dried to produce a uniform nanoparticle layer. Next, the substrate is precisely positioned under an optical subsystem using a set of coarse and fine nanopositioning stages. In the optical subsystem, laser light that has been patterned using a digital micromirror array is used to heat and sinter the nanoparticles into the desired patterns. This set of steps is then repeated to build up each layer of the 3D part in the μ-SLS system. Overall, this new technology offers the potential to overcome many of the current limitations in microscale additive manufacturing of metals and become an important process in microelectronics packaging applications.

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