Experimental study of phase transformation and specific heat of ternary zirconia-based oxides using differential scanning calorimetry

Characterization and compositional study of a ZrO2 engineering ceramic irradiated with a fibre laser beam

“…Phase transformation of the ZEC occurs when it is exposed to increasing/decreasing or changing temperatures as stated by Zakurdaev and Huang [27] and Luping et al [28]. With respect to the changing temperature being introduced during the laser surface treatment; it is important to understand the thermal effects of the laser radiation upon the crystal phases of the ZrO 2 ceramics.…”

Mathematical modelling of the fibre laser surface processing of a zirconia engineering ceramic by means of three-dimensional finite-element analysis

“…Considerable amount of research has also been conducted within the field of phase transformation of the ZrO 2 ceramics. The phase transformation of the ZrO 2 ceramic occurs when it is exposed to increasing/decreasing or changing temperatures as stated by Zakurdaev and Huang [24], Luping et al [25], and Holand and Beall [26]. With respect to the changing temperature being introduced during the laser surface treatment, it is important to understand the thermal effects of the laser radiation upon the crystal phases of the ZrO 2 ceramics.…”

Distribution of temperature during fibre laser radiation and effects thereon phase transformation of ZrO2 engineering ceramic

“…2). The processing gas used was Ar and was supplied at a flowrate of 25 L min 21 . To obtain an operating window, trials were conducted at a fixed spot size of 3 mm and by varying the power between 25 and 200 W, and varying the traverse speed between 25 and 500 mm min 21 .…”

“…The processing gas used was Ar and was supplied at a flowrate of 25 L min 21 . To obtain an operating window, trials were conducted at a fixed spot size of 3 mm and by varying the power between 25 and 200 W, and varying the traverse speed between 25 and 500 mm min 21 . From these trials it was found that 125 W at 100 mm min 21 was the ideal laser parameter to use in terms of achieving a crack-free surface.…”

“…To obtain an operating window, trials were conducted at a fixed spot size of 3 mm and by varying the power between 25 and 200 W, and varying the traverse speed between 25 and 500 mm min 21 . From these trials it was found that 125 W at 100 mm min 21 was the ideal laser parameter to use in terms of achieving a crack-free surface. All surfaces of the ZrO 2 engineering ceramic to be treated were marked with black ink coating before the fibre laser treatment to enhance the absorption and allow the laser beam to further penetrate into the surface of the ceramic, despite the fact that the near infrared wavelength of the fibre laser would generally absorb well into the semitransparent ZrO 2 engineering ceramic used.…”