The Manufacturing Of Cu-Al2O3 Composite Products: Study Of Process Parameters, Structure And Mechanical Properties

The purpose of this work is development of a method of producing the Cu-Al2O3 composite product by using the selective laser melting technology. The work includes 3 stages: production of composite powder, selective laser melting, mechanical tests of the obtained material. Method of production of composite powder has 2 stages: 1) production of metal powders by atomization of the liquid melt (Cu) in the gas jet, 2) modification of the surface of the metal particles of the second phase (Al2O3 nanopowder) in the planetary mixer. Metal powder was produced on URM-001 gas atomizer (patented by South-Ural State University). The surface modification of metal particles is produced in a planetary mixer KURABO Mazerustar kk250 with 5 different modes. Acceptable mode of modification is selected on the basis of the analysis of composite powders on a scanning electron microscope JSM-6400LV. The roundness of powders of Cu and Cu-Al2O3 determined using an optical analyzer OCCHIO 500. The conclusion is made about the suitability of powders for use in selective laser melting. The specimens of Cu and Cu-Al2O3 were made on the SINTERSTATION® Pro DM125 SLM machine by using different modes (power output, point distance, exposure time, hatch space). Surface end volume energy densities were used for describe of SLM modes. The structure of the composite material (Cu-Al2O3) using the chemical mapping was investigated on scanning electron microscopy. The mechanical tests on samples of Cu and Cu-Al2O3 made on the GLEEBLE 3800 Thermal-Mechanical Testing system.Published versio

Influence of Powder Characteristics on Processability of AlSi12 Alloy Fabricated by Selective Laser Melting

Selective laser melting (SLM) is one of the additive manufacturing technologies that allows for the production of parts with complex shapes from either powder feedstock or from wires. Aluminum alloys have a great potential for use in SLM especially in automotive and aerospace fields. This paper studies the influence of starting powder characteristics on the processability of SLM fabricated AlSi12 alloy. Three different batches of gas atomized powders from different manufacturers were processed by SLM. The powders differ in particle size and its distribution, morphology and chemical composition. Cubic specimens (10 mm × 10 mm × 10 mm) were fabricated by SLM from the three different powder batches using optimized process parameters. The fabrication conditions were kept similar for the three powder batches. The influence of powder characteristics on porosity and microstructure of the obtained specimens were studied in detail. The SLM samples produced from the three different powder batches do not show any significant variations in their structural aspects. However, the microstructural aspects differ and the amount of porosity in these three specimens vary significantly. It shows that both the flowability of the powder and the apparent density have an influential role on the processability of AlSi12 SLM samples

Influence of Powder Characteristics on Processability of AlSi12 Alloy Fabricated by Selective Laser Melting

Selective laser melting (SLM) is one of the additive manufacturing technologies that allows for the production of parts with complex shapes from either powder feedstock or from wires. Aluminum alloys have a great potential for use in SLM especially in automotive and aerospace fields. This paper studies the influence of starting powder characteristics on the processability of SLM fabricated AlSi12 alloy. Three different batches of gas atomized powders from different manufacturers were processed by SLM. The powders differ in particle size and its distribution, morphology and chemical composition. Cubic specimens (10 mm × 10 mm × 10 mm) were fabricated by SLM from the three different powder batches using optimized process parameters. The fabrication conditions were kept similar for the three powder batches. The influence of powder characteristics on porosity and microstructure of the obtained specimens were studied in detail. The SLM samples produced from the three different powder batches do not show any significant variations in their structural aspects. However, the microstructural aspects differ and the amount of porosity in these three specimens vary significantly. It shows that both the flowability of the powder and the apparent density have an influential role on the processability of AlSi12 SLM samples

Microstructure, Mechanical Properties, and Corrosion Behavior of 06Cr15Ni4CuMo Processed by Using Selective Laser Melting

A new class of martensitic stainless steel, namely 06Cr15Ni4CuMo, with applications in marine engineering, was processed by using selective laser melting (SLM). A body-centered cubic martensitic microstructure was observed, and the microstructure was compared with wrought 410 martensitic stainless steel. The SLM-processed sample showed a hardness of 465 ± 10 HV0.5, which was nearly 115 HV0.5 less than the wrought counterpart. Similarly, the SLM-processed sample showed improved YS and UTS, compared with the wrought sample. However, reduced ductility was observed in the SLM-processed sample due to the presence of high dislocation density in these samples. In addition, 71% volume high-angle grain boundaries were observed, corroborating the high strength of the material. The corrosion behavior was investigated in seawater, and the corrosion resistance was found to be 0.025 mmpy for the SLM-processed 06Cr15Ni4CuMo steel and 0.030 mmpy for wrought 410 alloys, showing better corrosion resistance in the SLM-processed material