Modelling and optimization of magnesium alloy milling parameters

In the pursuit to lighter, less consuming products, manufacturers, especially in aviation and automotive industries, are turning more and more to using lightweight alloys such as the ones based on magnesium. Higher requirements for increased productivity have led to concepts like high-speed machining (HSM), high feed machining (HFM) or high-efficiency machining. Tighter regulations concerning requiring for more environmentally friendly industrial processes led to limitations in the use of cooling liquids and a search for cooling methods with less impact (dry cutting, cryogenic cooling, near dry machining and others). Better machining processes can only be achieved by modelling and optimization. This paper briefly presents the results obtained by our research team concerning the modelling and optimization attempts on face milling of magnesium alloys using different methods: design of experiments (e.g. factorial design, response surface method), fuzzy logic or neural networks.

Plasma Metal Deposition for Metallic Materials

Plasma metal deposition (PMD®) is a promising and economical direct energy deposition technique for metal additive manufacturing based on plasma as an energy source. This process allows the use of powder, wire, or both combined as feedstock material to create near-net-shape large size components (i.e., >1 m) with high-deposition rates (i.e., 10 kg/h). Among the already PMD® processed materials stand out high-temperature resistance nickel-based alloys, diverse steels and stainless steels commonly used in the industry, titanium alloys for the aerospace field, and lightweight alloys. Furthermore, the use of powder as feedstock also allows to produce metal matrix composites reinforced with a wide range of materials. This chapter presents the characteristics of the PMD® technology, the welding parameters affecting additive manufacturing, examples of different fabricated materials, as well as the challenges and developments of the rising PMD® technology.

Mechanical Properites Of Fiber Laser Welded And Friction Stir (Spot) Welded Lightweight Alloys

Mechanical properties of fiber laser welded (FLWed), friction stir welded (FSWed), and friction stir spot welded (FSS weld) AZ31B-H24 Mg and Al 5754 alloys were studied. After welding, grains at the weld centre became recrystallized. β-Mg17A112 particles appeared in the fusion zone of the joints during laser welding, while a characteristic interfacial layer consisting of A112Mg17 and Al3Mg2 was observed in the A1/Mg dissimilar FSS weld. In FLWed joints, a joint efficiency of ~91% with superior yield strength, ultimate tensile strength and fatigue strength was achieved at a higher welding speed. In FSWed joints, a higher welding speed of 20 mm/s and lower rotational rate of 1000 rpm led to higher YS, but lower ductility, strain-hardening exponent and hardening capacity. In FSS weld joints, Mg/Mg, A1/A1 FSS welds and Al/Mg adhesive, Mg/A1 adhesive FSS welds had a significantly higher lap shear strength and fatigue life than the A1/Mg FSS weld.

Mechanical Properites Of Fiber Laser Welded And Friction Stir (Spot) Welded Lightweight Alloys

Mechanical properties of fiber laser welded (FLWed), friction stir welded (FSWed), and friction stir spot welded (FSS weld) AZ31B-H24 Mg and Al 5754 alloys were studied. After welding, grains at the weld centre became recrystallized. β-Mg17A112 particles appeared in the fusion zone of the joints during laser welding, while a characteristic interfacial layer consisting of A112Mg17 and Al3Mg2 was observed in the A1/Mg dissimilar FSS weld. In FLWed joints, a joint efficiency of ~91% with superior yield strength, ultimate tensile strength and fatigue strength was achieved at a higher welding speed. In FSWed joints, a higher welding speed of 20 mm/s and lower rotational rate of 1000 rpm led to higher YS, but lower ductility, strain-hardening exponent and hardening capacity. In FSS weld joints, Mg/Mg, A1/A1 FSS welds and Al/Mg adhesive, Mg/A1 adhesive FSS welds had a significantly higher lap shear strength and fatigue life than the A1/Mg FSS weld.

Experimental investigation on the effect of platform heating on the dynamic mechanical properties of selective laser manufacturing of AlSi10Mg alloy

Additive manufacturing (AM) is one of the emerging promising technology technologies of manufacturing prototypes. The process of AM is based on melting powder by an energetic beam layer by layer to create a three-dimensional body. One of the lightweight alloys that is being used for AM is AlSi10Mg. The process of manufacturing is controlled by several tens of parameters most of which are determined by the machine manufacturer. One of the important parameters is the building platform temperature. In the present study we took samples from different heights of the building platform and measured the dynamic mechanical properties of each sample. It was noted that after a stress relief treatment (SRT) the difference in the static and dynamic mechanical properties along the building direction changed differently. The dynamic mechanical properties of samples that were fabricated in proximity to the building platform did not change after the SRT, while the mechanical properties of the samples that were fabricated far from the platform changed dramatically and became like those that were fabricated near the building plate.