Papers by Author: H.L. Liu

Abstract: A floor typed spatial robot of abrasive water jet machining is designed, which can be applied to machine three-dimensional complicated work-pieces. Its merits are simple structure and flexible moving. The structure and transmission programmer are discussed in detail. The working range of the abrasive water jet robot is analyzed to meet the need of the various sized work-pieces. The motion of the each joint is realized by means of various transmission programmers. The precise movement of the robot is realized by the stepping motor, and the required power of the robot is calculated.

Abstract: High pressure abrasive water jet (HPAWJ) machining has many advantages in hard brittle material processing. In this paper, the hole formation on stone by HPAWJ is analyzed based on brittle and plastic fracture theories. The formation and construction of jet are studied. The distribution of jet velocity, abrasives and energy in the jet-beam section of HPAWJ is analyzed. It is shown that the cross-section of the hole is characterized by a ‘Reverse-bell’ shape on stones by a HPAWJ. The jet velocity of HPAWJ gets lower from jet center to jet margin and it’s distribution is consistent with normal distribution function along with jet center. The concentration of abrasives becomes smaller from jet margin to jet center and it’s distribution is consistent with normal distribution function along with jet margin. The distribution of jet velocity, abrasives and energy in the section of HPAWJ is modeled.

Abstract: The milling experiments of the annealed T10A steel were carried out in the various cutting conditions using the coated cemented carbide tool. The cutting parameters were designed by the multi-factor orthogonal experiment method, and the effects of cutting speed, feed, axial depth of cut and radial depth of cut on the cutting force and tool wear were investigated. The tool wear mechanisms were also discussed. Adhesion, abrasion, diffusion and oxidation were the main tool wear mechanisms. According to these investigations, the optimizing cutting parameter was recommended.