||Effect of Laser Emission Parameters on Mechanical and Physical Properties of Cast Pure Titanium
2014p.862305 , 2015-03-20 , Hindawi Publishing Corporation
The objective of this study was to investigate the effect of laser beam parameters on the mechanical and physical properties of cast commercially pure titanium. Dumbbell-shaped test specimens (ISO6871) were cast with ASTM grades 2 and 3 Ti. The cast surfaces were laser-treated with various laser emission parameters (current: 200, 220, and 240 A; spot diameter: 1.0, 1.6 mm; pulse duration: 10, 1 ms) under argon shielding. Tensile testing was conducted at a crosshead speed of 1.0 mm/min. Data of tensile strength and elongation were statistically analyzed using ANOVA/Tukey's test (=0.05). Hardness depth profiles were made with cross sections of rod-shaped specimens after laser treatments. Control specimens without laser treatment were also prepared. The laser-treated specimens showed significantly higher tensile strengths than those of control specimen for both grades 2 and 3 Ti. The specimens treated with 1.0 mm spot diameter indicated higher tensile strengths than those treated with 1.6 mm spot diameter for both currents (200 A and 240 A). The laser treatment decreased the subsurface hardness and increased the hardness between 75 m and 400 m in depth when compared to the hardness of control specimens. Laser surface treatment for cast commercially pure titanium modified integrity of cast surface and significantly improved mechanical and physical property.