Papers by Keyword: Sticking Failure

Abstract: The large hydrogenated cylindrical shell is an important part of petrochemical pressure vessels. From the macroscopic aspects, the influence that the surface defects of the large hydrogenated cylindrical shells forging blank has on the high efficiency machining was analyzed in the paper firstly. Then, through the chemical point of view, the new chemical components of the shells material were known, and the shells material physical properties were also dissected. The phenomenon of compatibility between the Co element which is in tools material and the siderophile element of the 2.25Cr-1Mo-0.25V steel which is the material of the large hydrogenated cylindrical shell was found. Therefore, the technical performance requirements of the heavy-duty turning tool which is to achieve the goal of high efficiency cutting were put forward. Through researching the chemical and the physical properties of the shell, the new high-efficiency turning tool was designed from the aspects of the tools material and the tools geometric structure. Finally, the comparative test between the new heavy-duty turning tool which was named XF8 and the YT5 tool which was being used in factory was made, and by way of comparing both the service life and the chip-breaking performance of XF8 with YT5s, the test results showed that the XF8 met the requirements of high-efficiency heavy-duty turning, and the feasibility of the tools design scheme was further verified.

Abstract: As an important part of MEMS, the micro-comb electrostatic driving structure is the main source of mechanical movement in many MEMS devices. Its reliability will directly affect the using performance of the MEMS devices. The electrostatic driving system of micro-comb capacitive micro-machined gyroscope can be equivalent to a second order system. If the applied voltage is less than the pull-in voltage, the movable micro-comb will maintain a steady state. Otherwise, the micro-combs will stick together because the applied voltage is greater than the calculated pull-in voltage. If the distance between micro-combs is too narrow, the role of these micro forces will be very significant. The pull-in phenomenon occurring in the process that the micro-machined gyroscope is applied on a phase step input voltage will lead to the very narrow comb spacing. As a result that the role of micro-forces such as the capillary force, Van der Waals force and Casimir force will become very significant, and the micro-combs will stick together permanently.

Abstract: Through the analysis on damaged tool in sticking failure experiment by cutting austenitic stainless steel (1Cr18Ni9Ti) with scanning electron microscopy (SME), found that there are micro cracks existent on rake face near the tip of the cutting tool, through the research of the emergence, development and distribution direction of the crack, the direct reason for tool breakage is the crack being out of control. Combining the study of cutting tool element density change in cutting zone and grooving wear on rake face, this paper analyzed the cause of the binding between chip and tool and the influence factors of sticking failure during the cutting process.

Abstract: The problem of Sticking Failure of cutting tool is serious for cutting stainless steel 1Cr18Ni9Ti, on the basis of the Sticking Failure orthogonal experiment of YG8, it researches the range of temperature for Sticking Failure, chooses the best cutting parameters, and researches the effect for Sticking Failure, which provides the academic basis for the study of criterion of the mechanism of Sticking Failure.