Advanced Materials Research Vols. 317-319

Abstract: Giant magnetostrictive actuator is ideal for fast precision Alignment, but the nonlinear strain caused by temperature rise has serious impact on the control precision. This paper verifies the impact of strain caused by temperature rising on the experimental method, based on analyzing the principle of the giant magnetostrictive actuator. The copper consumption in giant magnetostrictive actuator coil , the iron consumption in the magnetostrictive rod and the corresponding method of inhibiting temperature rise were analyzed by theoretical analysis and finite element simulation.

Abstract: Aiming at the poor condition of high chromium casting iron hammerhead longevity, developing high vanadium casting iron hammerhead, producing it by metal mould, and passing more than 10,000 tons production testing.

Abstract: TDI as main isocyanate, IPDI as end-capping reagent, waterborne polyurethane (WPU) surface-sizing agent have been obtained by a pre–polymerization process. WPU were mixed with starch SSA in different proportion and a composite sizing agent obtained. It is indicated the water resistance, gloss and folding resistance of WPU/starch sized papers are much higher than starch sized papers. The ink absorption obviously decreases and the mechanical properties wholly increase. WPU/starch composite emulsions is a new kind of surface sizing agent having broad development prospects.

Abstract: The CCT curve and TTT curve of as-cast 42CrMo steel were precisely simulated by using JmatPro software. The quenching process(which is as follow: quenching at 860°C by AQ251 quenching liquid and cooling to 200°C) was given by analysizing the CCT curve. The quenching microstructure, hot-stress field and hardness after quenching were simulated by using the Deform-HT module The results were obtained as follows:(1)The microstructure of the materials is martensite+bottom bainite at the surface and pearlite+ferrite at the centure.(2)The surface hardness and central hardness were separately 51.3 and 28.5 HRC. The metallographic observation and hardness experiment were done and the results of numerical simulation was finally verified.

Abstract: This paper developed a new type of ball-type porous metal preparation method. A brief introduction of this new type of spherical aluminum-based metal forming method of porous, pore structure and its compression and energy absorption properties, but also involves the performance of spherical holes iron foam.

Abstract: This paper studies the chemical mechanical polishing (CMP) of the wafer's material such as stainless steel, monocrystalline silicon etc, and analyzes how the technological parameters’ impact on the final wafer’s surface material removal rate, surface quality and surface damage like the polishing pad’s speed and the wafer speed, polishing pressure and polishing time.The results show that: when the difference between the polishing pad's rotation speed and the wafer's rotation speed is small and their directions are the same , then the material removal rate of the wafer is larger.when the polishing pressure is selected between 5 to 6.5 kPa, the wafer surface's damage is smaller.The polishing time also play a very important role and affect the surface quality and surface damage of the wafer after polishing.

Abstract: Cement-stabilized soil has been widely used to ground treatment, tracing of foundation pit, water resistance. Additives in cemented soil play an important role in improving its basic properties of cemented soil. In this paper, a new kind of additive, Nanometer Silicon Oxide (SiO2-x), was incorporated into cemented soil. Undrained triaxial compression tests were performed to discuss the reinforced effect of the nanometer silicon on the strength property of the cemented soil. Four main factors that influence the compressive strength of the nanometer silicon cemented soil (NCS) are considered: cement content, nanometer material content, confining pressure, and water\cement ratio. Based on orthogonal tests, the paper analyzed quantitatively the main influence factors of the compression strength of NCS and presented the optimum mix combination. A linear regression model for the compression strength were proposed. Finally, some conclusions have been achieved.

Abstract: By fitting the calculated transformed fraction according to developed phase-transformation model to the experimental data obtained by differential dilatometry, the kinetic characteristics of the austenitization process in T91 steels have been investigated. According to the kinetic parameters fitted, we recognize that the nucleation and growth of austenite grain are mainly controlled by the diffusion of carbon in ferritic and austenite respectively. In addition, by increasing the diffusion active energy of carbon in austenite, carbides hinder the motion of interface and thus refine austenite grain.

Abstract: Adopting domestic polytetrafluoroethylene (PTFE) turning plate as materials, a new isosceles triangle macroporous mesh was designed. The correspond mould and the special fixtures for continuous punching of ultra-thin plastic sheet were successfully developed. The PTFE mesh was manufactured through computer numerically controlled (CNC) punch. In terms of electronic universal testing machines and microcomputer differential thermal balance, mechanical properties and thermostability of the PTFE mesh were studied. The results indicated that the tensile strength of PTFE mesh is 11.98 MPa which is greater than the literature value of 7.77 MPa, and its heat-resisting performance is excellent without decomposition prior to 312 oC.