scholarly journals Combined effect of surface anomalies and volumetric defects on fatigue assessment of AlSi7Mg fabricated via laser powder bed fusion

2020 ◽  
Vol 34 ◽  
pp. 100918 ◽  
Author(s):  
Milad Hamidi Nasab ◽  
Simone Romano ◽  
Dario Gastaldi ◽  
Stefano Beretta ◽  
Maurizio Vedani
Keyword(s):  
Combined Effect ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Fatigue Assessment ◽  
Powder Bed ◽  
Effect Of Surface

scholarly journals Effect of Surface and Subsurface Defects on Fatigue Behavior of AlSi10Mg Alloy Processed by Laser Powder Bed Fusion (L-PBF)

Metals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1063 ◽  
Author(s):  
Milad Hamidi Nasab ◽  
Alessandro Giussani ◽  
Dario Gastaldi ◽  
Valeria Tirelli ◽  
Maurizio Vedani
Keyword(s):  
Crack Nucleation ◽  
Fatigue Behavior ◽  
Fatigue Behaviour ◽  
Surface Finishing ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Finishing Processes ◽  
Effect Of Surface ◽  
Subsurface Defects

The fatigue behaviour of an AlSi10Mg alloy processed by laser powder bed fusion (L-PBF) and subjected to different surface finishing processes was investigated paying special attention to the residual defects on the surface and the dominant fatigue failure mechanisms. Roughness measurements and qualitative surface morphology analysis showed smooth surfaces in the case of vibro-finishing and machining followed by polishing. The fatigue performance did not reveal to be directly related to surface roughness, but residual intrusions left on the finished surfaces. Post-mortem analysis showed single- or multiple-crack nucleation from pores opened on the surface, un-melted powders, or spatters considered as typical L-PBF defects. A fatigue limit of 195 MPa for machined and polished samples was obtained by substantial removal of surface and subsurface defects.

scholarly journals Effect of Surface Sandblasting and Turning on Compressive Strength of Thin 316L Stainless Steel Shells Produced by Laser Powder Bed Fusion

Metals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1070
Author(s):  
Bharat Mehta ◽  
Eduard Hryha ◽  
Lars Nyborg ◽  
Frederic Tholence ◽  
Erik Johansson
Keyword(s):  
316L Stainless Steel ◽  
Surface Condition ◽  
Surface Region ◽  
Powder Bed Fusion ◽  
Processing Conditions ◽  
Laser Powder Bed Fusion ◽  
Microstructural Investigation ◽  
Powder Bed ◽  
Compressive Performance ◽  
Effect Of Surface

This study evaluates the effect of post-manufacturing treatment on the compressive performance of additively manufactured components. The components were thin cylindrical shells with an aspect ratio of 25:1 manufactured using laser powder bed fusion and that were then surface treated by means of sandblasting or turning. The as-printed and subsequently surface treated samples were uniaxially compressed until failure to depict the effect of the surface condition on the compressive mechanical behavior. The results show that as the surfaces became smoother via sandblasting, the average peak strength for buckling load improves negligibly (0.85%), whereas this effect reaches 6.5% upon surface layer removal via turning. Through microstructural investigation and co-relating this with an understanding of processing conditions existing in manufacturing itself, this effect is seen to be linked to contour scanning causing softening of the surface region in a component.

scholarly journals On the Relevance of Volumetric Energy Density in the Investigation of Inconel 718 Laser Powder Bed Fusion

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 538 ◽  
Author(s):  
Fabrizia Caiazzo ◽  
Vittorio Alfieri ◽  
Giuseppe Casalino
Keyword(s):  
Surface Roughness ◽  
Energy Density ◽  
Process Parameters ◽  
Vickers Hardness ◽  
Powder Bed Fusion ◽  
Processing Conditions ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Fractional Density ◽  
Experimental Variation

Laser powder bed fusion (LPBF) can fabricate products with tailored mechanical and surface properties. In fact, surface texture, roughness, pore size, the resulting fractional density, and microhardness highly depend on the processing conditions, which are very difficult to deal with. Therefore, this paper aims at investigating the relevance of the volumetric energy density (VED) that is a concise index of some governing factors with a potential operational use. This paper proves the fact that the observed experimental variation in the surface roughness, number and size of pores, the fractional density, and Vickers hardness can be explained in terms of VED that can help the investigator in dealing with several process parameters at once.

Heat source model calibration for thermal analysis of laser powder-bed fusion

2020 ◽  
Vol 106 (7-8) ◽  
pp. 3367-3379 ◽  
Author(s):  
Shahriar Imani Shahabad ◽  
Zhidong Zhang ◽  
Ali Keshavarzkermani ◽  
Usman Ali ◽  
Yahya Mahmoodkhani ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Heat Source ◽  
Model Calibration ◽  
Source Model ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Heat Source Model ◽  
Powder Bed

scholarly journals The Effect of Cu Content and Surface Finish on the Metal Dusting Resistance of Additively Manufactured NiCu Alloys

2021 ◽  
Author(s):  
Katrin Jahns ◽  
Anke S. Ulrich ◽  
Clara Schlereth ◽  
Lukas Reiff ◽  
Ulrich Krupp ◽  
...  
Keyword(s):  
Surface Finish ◽  
Powder Bed Fusion ◽  
Metal Dusting ◽  
Laser Powder Bed Fusion ◽  
Roughness Measurement ◽  
Powder Bed ◽  
Cu Content ◽  
Binary Model ◽  
Interesting Candidate ◽  
Nicu Alloys

AbstractDue to the inhibiting behavior of Cu, NiCu alloys represent an interesting candidate in carburizing atmospheres. However, manufacturing by conventional casting is limited. It is important to know whether the corrosion behavior of conventionally and additively manufactured parts differ. Samples of binary NiCu alloys and Monel Alloy 400 were generated by laser powder bed fusion (LPBF) and exposed to a carburizing atmosphere (20 vol% CO–20% H2–1% H2O–8% CO2–51% Ar) at 620 °C and 18 bar for 960 h. Powders and printed samples were investigated using several analytic techniques such as EPMA, SEM, and roughness measurement. Grinding of the material after building (P1200 grit surface finish) generally reduced the metal dusting attack. Comparing the different compositions, a much lower attack was found in the case of the binary model alloys, whereas the technical Monel Alloy 400 showed a four orders of magnitude higher mass loss during exposure despite its Cu content of more than 30 wt%.

Sign in / Sign up

Export Citation Format

Share Document