Neutron computed tomography investigation of the porosity on the titanium femoral knee investment casting

Abstract

Rotational velocity in the centrifugal casting is one of the factors that affect to the porosity of the femoral knee cast. The objective of this research is to investigate the internal porosity of as-cast femoral knee prostheses. CP-titanium femoral knee was cast using vertical centrifugal investment casting. The three rotational velocities parameter utilized in the vertical centrifugal casting were 45, 55 and 65 rpm. Neutron computed tomography characterization was conducted to investigate the size, percentage, and location of pores. The maximum size of pores in casting with the rotational velocity of 45, 55, and 65 rpm are 14.78 mm3, 14.98 mm3, and, 14.65 mm3, respectively. The percentage of pores in the casting with the rotational velocity of 45, 55, and 65 rpm are 1.78%, 2.78% and, 1.78% respectively. The size and percentage of the pores for casting at the rotational velocity of 65 rpm are smaller than the size and percentage of the casting at 45 and 55 rpm.