Advanced Materials Research Vols. 199-200

Abstract: To improve the hot-rolled processing rate and mechanical properties of Monel alloy plates, its hot-rolling and heat treatment technics were researched, and reasonable hot-rolling temperature and annealing temperature were designed. Through the hot-rolling tests of Monel alloy plates ingots under the condition of different temperatures with a hot-rolling mill, the true stress and true strain curves were measured, the regularity of the flow stress influenced by temperature was investigated, and the hot-rolling temperature was ensured. We also did some study on the effects of annealing temperature on the mechanical properties and metallographs. The results show the reasonable hot-rolling temperature of Monel alloy plates ranges between 1050°C and 1150°C, and its annealing temperature ranges between 650°C and 750°C.

Abstract: Four specifications TP2 copper tubes experienced in-line induction annealing test was studied, mechanical properties of the tubes and the influencing factors were analyzed. The results show that mechanical properties and microstructure of different positions are stable and homogeneous after in-line induction annealing. Mechanical properties of the specimens are not only related to internal factors, but also related to external factors such as environmental temperature.

Abstract: The semi-solid 6061 alloy was obtained with method of alternating electromagnetic stirring. The results show that compared with horizontal, vertical and spiral magnetic stirring method, alternating magnetic stirring could make eligible slurry with finer, more equiaxed and more homogeneous primary α particles in much shorter time. The microstructure evolution during isothermal treatment is studied and it is shown that the average particle diameter increases with the increase of isothermal holding time and the shape coefficient decreases somewhat at first, and then decreases sharply in the end.

Abstract: In this paper, a machining method of deep hole on the nickel-based high-temperature alloy using the pulse electrochemical machining is proposed. The effect of five technological parameters on the depth-averaged radial overcut of the hole to be machined in the machining process is discussed; then the mathematical model is built, and the effect of parameters on the overcut is illustrated. The speed ratio is determined to judge the quality and the processing performance of holes. The technological parameters adopted in the experiment, can be used to produce effectively high-quality hole of big proportion of depth to diameter on the nickel-based high-temperature alloy in the machining process.

Abstract: Isothermal constant strain rate compression tests on high-carbon steel are carried out under deformation temperation of 850°C, 950°C, 1050°C、1150°C and 1250°C respectively and deformation of 0.7 using the THERMECMASTOR-Z thermal simulator at a strain rate of 1s-1. The austenite grain morphology before and after deformation and the true stress-strain curves during the deformation process are analyzed. The experimental results show that increased deformation temperation can obviously contribute to the grain refinement. And under the same strain rate conditions, as the deformation temperation rises, peak stress will move toward the opposite direction of strain increment，thus the dynamic recrystallization is apt to occur.

Abstract: Spiral bevel gear milling machine is one typical representative of complex manufacturing equipments. In order to simulate spiral bevel gear cutting, a five-axis virtual CNC gear cutting machine under VERICUT software is established in this paper. Based on a spiral bevel gear generating theory, the surface forming of the spiral bevel gear is studied by using coordinate transformation method in spatial kinematics, and the G-code required by actual gear cutting is generated. Then, according to the properties of the general five-axis CNC system, the machine model and the relevant configuration parameters under VERICUT is created, so the spiral bevel gear virtual NC machining system is set up. Finally, the cutting simulation and crash examination are accomplished under VERICUT. By using this method, the accuracy of the bevel gear cutting system based on a general five-axis CNC can be well verified.

Abstract: The microstructure and properties of Cu-0.4wt%Cr alloys prepared by a shortened process and a conventional process were investigated by means of optical microscopy (OM), transmission electron microscopy (TEM), hardness testing and electrical conductivity measurement. After online hot rolling- quenching and cold rolling with 60% reduction and then aging at 450°C for 30min (process A), and solution treatment - cold rolling with 60% reduction - aging 450°C for 60min (process B), good properties combination of the alloys are obtained, and the hardness and electrical conductivity reach to 156HV, 86.4%IACS and 169HV, 81.1%IACS, respectively, and the shortened process (A) is suitable for commercial copper strip production. Plenty of fine and dispersed precipitates are responsible for the hardness and electrical conductivity improvement of the alloys. The difference of properties between process A and B is resulting form the difference of effective precipitates volume fraction under the various processes.

Abstract: An assemblability evaluation system of products including parts and subassemblies was presented. The necessity about assemblability evaluation for subassemblies was discussed. A subassembly-centered product assemblability analysis method was proposed. The two-step assemblability analysis flow including process step and entire step about subassembly was designed, which can analyze structure of subassembly when it was assembled and fitted on product. A web-based prototype system of subassembly-centered product assimilability evaluation which supports multi-sited collaborative design was developed with Java/JSP, which integrated with the platform of collaborative assembly planning and collaborative assembly simulation. Finally, an example was used to validate reasonability of subassembly assemblability analysis method and the effectiveness of the evaluation system.

Abstract: To satisfy the local forming need of sheet-metal part, numerical simulation of SUS304 stainless steel deep-drawing with trilateral constrained slot were carried out by employing the analytical software ETA/dynaform5.5. The influence of different friction coefficient and holder force on the forming quality was analyzed by taking the inflow volume while parts forming 50mm as standard. The results show that the effect of trilateral constraint on the uneven flow and deformation of flange. And some measures were illustrated to improve the quality of some of these parts.

Abstract: To study the influence of fining temperature on glass qualities, different fining temperatures from 1400°C to 1500°C were used to prepare a series soda-lime-silica glass with identical chemical compositions. Infrared spectroscopy was used to determine the water content of glass, general analyzer of melt physical properties was used to study the viscosity and surface tension change of glass melt, microscope was carried out find glass bubbles, wet chemical analyses were used to determine the Fe²⁺/(Fe²⁺+Fe³⁺) ratio. The results show that, generally, with the increase of fining temperature, the glass melt’s water content, bubbles number and Fe²⁺/(Fe²⁺+Fe³⁺) ratio increase, viscosity decreases. Particularly, when the fining temperature is 1450°C, the glass has lowest water content, bubbles number, Fe²⁺/(Fe²⁺+Fe³⁺) ratio, and viscosity, and its surface tension is largest. Among all tested fining temperature, 1450°C is the optimal fining temperature.