Abstract: The invention relates to a surface gradient cross-linked method of a ultra-high molecular weight polyethylene and the application thereof. The surface gradient crosslinked method of ultrahigh molecular weight polyethylene includes a n ultra-high molecular weight polyethylene surface photoinitiator diffusion step and an ultraviolet light irradiation crosslinking step. In this method, the photoinitiator is diffused deeply into the surface of ultra-high molecular weight polyethylene, the body material shows a gradient cross-linking from the surface to the inside after ultraviolet irradiation so that the whole bulk has a high toughness and the surface there of has a high wear resistance.

Abstract: A method of making an implant having a porous portion is disclosed. The method comprises the following steps: obtaining an artificial foam containing porous portion; scanning the artificial foam to obtain a digital porous model; editing the digital porous model; assembling the digital porous model to form a digital porous block; editing the digital porous block to obtain a digital implant model; forming the implant by printing the digital implant model through a 3D printer. An implant and a method of calculating porosity a porosity of a porous material are also disclosed.