scholarly journals Evaluation of the Microstructure and Mechanical Properties of a New Modified Cast and Laser-Melted AA7075 Alloy

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3430 ◽  
Author(s):  
Asmaa M. Khalil ◽  
Irina S. Loginova ◽  
Andrey V. Pozdniakov ◽  
Ahmed O. Mosleh ◽  
Alexey N. Solonin
Keyword(s):  
Mechanical Properties ◽  
Corrosion Resistance ◽  
Melting Process ◽  
Scanning Speed ◽  
Elemental Distribution ◽  
Transition Elements ◽  
Laser Melting ◽  
Melted Zone ◽  
Microstructure And Mechanical Properties ◽  
Standard Alloy

The mechanical properties and microstructure of as-cast and homogenized AA7075 were investigated. This alloy was modified by adding transition elements 0.3%Sc + 0.5%Zr, 1%Ti + 0.2%B, and 1%Fe + 1%Ni for use in additive manufacturing applications. After adding Ti + B and Sc + Zr, the structure became uniform and finer with the formation of the Al3(Sc, Zr) and TiB2 phases. Coarse structures were obtained with the formation of an extremely unfavorable morphology, close to a needle-like structure when Fe + Ni was added. The mechanical properties of the modified alloys were increased compared to those of the standard alloy, where the best ultimate tensile strength (UTS) and yield strength (YS) were obtained in the AA7075-TiB alloy compared to the standard alloy in as-cast and homogenized conditions, and the highest hardness value was provided by Fe + Ni additives. The effect of the laser melting process on the microstructure and mechanical properties was investigated. Single laser melts were performed on these alloys using 330 V and a scanning speed of 8 mm/s. During the laser melting, the liquation of the alloying elements occurred due to non-equilibrium solidification. A change in the microstructures was observed within the melt zone and heat-affected zone (HAZ). The hardness of the laser-melted zone (LMZ) after adding the modification elements was increased in comparison with that of the standard alloy. Corrosion testing was performed using a solution of 100 mL distilled water, 3.1 g NaCl, and 1 mL HCl over 5, 10, and 30 min and 1 and 2 h. The corrosion resistance of the alloy modified with FeNi was low because of the non-uniform elemental distribution along the LMZ, but in the case of modification with ScZr and TiB, the corrosion resistance was better compared to that of the standard alloy.

Investigation of selective laser melting process for Cu-5Sn alloy on surface roughness, microstructure and mechanical property

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Peng Yang ◽  
Dingyong He ◽  
Zengjie Wang ◽  
Zhen Tan ◽  
Hanguang Fu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Surface Roughness ◽  
Selective Laser Melting ◽  
High Strength ◽  
Melting Process ◽  
Scanning Speed ◽  
Laser Melting ◽  
Forming Process ◽  
Content Type

Purpose In this research, the highly dense bulk Cu-5Sn alloy specimens were fabricated using selective laser melting (SLM). This study aims to establish the relationship between laser power (LP), scanning speed (SS) and hatch space (HS) with surface roughness (Ra) and density. To obtain Cu-5Sn alloy formed parts with high strength and low surface roughness. The microstructure and mechanical properties of SLMed Cu-5Sn were investigated. Design/methodology/approach The relative density (RD) was optimized using the response surface method (RSM) and analysis of variance. First, the Ra of SLMed formed specimens was studied to optimize the forming process parameters with a good surface. Then, the dense specimens were studied by ANOVA and the RSM to obtain dense specimens for mechanical property analysis. Findings Dense specimens were obtained by RSM and ANOVA. The tensile properties were compared with the casted specimens. The yield and ultimate strengths increased from 71 and 131 MPa for the cast specimens to 334 and 489 MPa for the SLMed specimens, respectively. The ductility increased significantly from 11% to 23%, due to the refined microstructure of the SLMed specimens, as well as the formation of many twin crystals. Originality/value The Ra, RD and mechanical properties of SLM specimens Cu-5Sn were systematically studied, and the influencing factors were analyzed together. This study provides a theoretical and practical example to improve the surface quality and RD.

scholarly journals Densification, Microstructure, and Mechanical Properties of Additively Manufactured 2124 Al–Cu Alloy by Selective Laser Melting

Materials ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4423
Author(s):  
Junwang Deng ◽  
Chao Chen ◽  
Wei Zhang ◽  
Yunping Li ◽  
Ruidi Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Selective Laser Melting ◽  
Hollow Structure ◽  
Base Plate ◽  
Scanning Speed ◽  
Processing Parameters ◽  
Laser Melting ◽  
Cu Alloy ◽  
Microstructure And Mechanical Properties ◽  
Hatch Spacing

Owing to its high specific strength and low density, Al–Cu alloys have been extensively used in aerospace for lightweight components. Additive manufacturing techniques such as selective laser melting, which offers geometric freedom, is suitable for topology-optimized designs. In this study, the effect of processing parameters on the densification, microstructure, and mechanical properties of additively manufactured Al–Cu alloy 2124 by selective laser melting was investigated. Parameters such as laser power, scanning speed, hatch spacing, and use of a support were studied. The results revealed that a grille support with a hollow structure played a resistant role in the transfer of heat to the base plate, thus reducing the temperature gradient and lessening cracks in the building part. Smaller hatch spacing was beneficial for the achievement of a higher relative density and strength due to track re-melting and liquid phase backflow, which could fill cracks and pores during the building process. An ultimate tensile strength as high as 300 MPa of the vertically built sample was obtained at optimized processing parameters, while the elongation was relatively limited. Moreover, columnar grains were found to be responsible for the anisotropy of the mechanical properties of the as-printed 2124 alloy.

scholarly journals On the Effect of Selective Laser Melting Process Parameters on the Microstructure and Mechanical Properties of Al Alloys

2018 ◽  
Author(s):  
Ahmed Maamoun ◽  
Yi Xue ◽  
Mohamed Elbestawi ◽  
Stephen Veldhuis
Keyword(s):  
Mechanical Properties ◽  
Selective Laser Melting ◽  
Process Parameters ◽  
High Strength ◽  
Melting Process ◽  
Laser Melting ◽  
Influence Of Process Parameters ◽  
Microstructure And Mechanical Properties ◽  
Wide Range

Additive manufacturing (AM) offers customization of microstructure and mechanical properties of fabricated components according to the material selected, and process parameters applied. Selective laser melting (SLM) is the commonly used technique for processing high strength aluminum alloys. Selection of SLM process parameters could control the microstructure of parts and their mechanical properties. However, the process parameters limit and defects obtained inside the as-built parts present obstacles to customized part production. This study investigates the influence of SLM process parameters on the quality of as-built Al6061 and AlSi10Mg parts according to the mutual connection between the microstructure characteristics and mechanical properties. The microstructure of both materials was characterized for different parts processed over a wide range of SLM process parameters. The optimized SLM parameters were investigated to eliminate the internal microstructure defects. The behaviour of mechanical properties of parts was presented through regression models generated from the design of experiment (DOE) analysis for the results of hardness, ultimate tensile strength, and yield strength. A comparison between the results obtained and that reported in the literature is presented to illustrate the influence of process parameters, build environment, and powder characteristics on the quality of parts produced. The results obtained from this study could help to customize the part’s quality by satisfying their design requirements in addition to reducing the as-built defects which in turn reduce the amount of the post-processing needed.

UGIMA 4404, UGIMA 316L

Alloy Digest ◽  
1998 ◽  
Vol 47 (12) ◽  
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Corrosion Resistance ◽  
Melting Point ◽  
Physical Properties ◽  
Melting Process ◽  
Heat Treating ◽  
Aisi 316L

Abstract UGIMA 4404 (UGIMA 316L) is identical to UGINE 4404 (AISI 316L) in analysis, corrosion resistance, mechanical properties, and forging and welding ability, but not with respect to machinability. A specific melting process creates inclusions of malleable oxides with a low melting point. The inclusions improve machinability by 20-30% compared with AISI 316L (1.4404) stainless steel. This datasheet provides information on composition and physical properties. It also includes information on corrosion resistance as well as heat treating, machining, and joining. Filing Code: SS-735. Producer or source: Ugine-Savoie.

Sign in / Sign up

Export Citation Format

Share Document