Key Engineering Materials Vols. 407-408

Abstract: . In this paper, the model of fixed abrasive diamond wire saw has been set up, and its cutting mechanism has been discussed. Then, the material removal rate model and wire saw cutting efficiency model have been established. the speed of wire saw, the number of the dynamic effective abrasive and the workpiece feed rate have been analyzed to study their impaction on the stability of cutting process. Finally, some rules and suggestions were brought forward.

Abstract: This study deals with the influence of laser hardening for a carbon steel AISI 1045 on machinability in turning. Turning test was conducted for the purpose to clarify the influence of laser hardening for steel surface on the chip controllability and surface roughness. In turning laser hardened steel, continuous chip is broken in the laser hardened zone during cutting due to higher brittleness. The broken chips have spiral form and their length is approximately equal to those generated by less than 10 revolution cutting. The surface roughness shows slightly lower compared with non-laser hardened steel.

Abstract: Ultrafine-grained treatment (multiple forging and heat treatment) were carried out on FGH4096 alloy to get ultrafine grain with grain being of 1-5μm. OM, SEM, TEM and tensile test were used to study the action of ultrafine-grained treatment on improving structure and properties. The tensile properties of the alloy processed under ultrafine-grained treated have shown quite satisfactory levels, which ultimate strength (UTS) reach 1730Mpa and yield strength (YS) values reach 1470Mpa at room temperature. The apperance of advanced strength has originated chiefly form not only the persence of fine grains, but also structure of grain boundaries and diaperce pricipitations of secondary phase. A better combination of mechanical properties achieved by use of ultrafine-grained treatment makes it possible to explore the dual property turbine disc to its maximum potential for FGH 4096 alloy.

Abstract: The nano-composite electroless coating was introduced into bio-limited forming technology for the first time, and the feasibility of the nano-composite electroless coating on microorganism was verified. The composite coated microorganism was analyzed by using optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The results showed that stirring method would make significant effect on the content of nano-particles in the composite coating. And compared with mechanical stirring, the magnetical stirring makes the content of Fe in the composite coating increase almost twice. The co-deposition mechanism of the composite coating was also discussed.

Abstract: : The effect of different surface topography on stress distribution of vacuum plate glass for the aluminum alloy braced pillars was analyzed by electrometric method. The results show that the maximum stress exists at the interfaces of all experimental glasses sheet and the top and bottom sides of a brace. The conclusion that the size of contact area between braced pillar and glass has an impact on stress distribution of the glass is obtained. The stress-strain field of different vacuum plate glasses was analyzed by the finite element method. The stress distribution of their important sides was obtained such as sealing side, supporting side and braced pillar. The experimental results are shown that high precision of the brace height and good flatness of the glass sheet considerably improve vacuum plate glass quality，such as its strength，its dependability and service life.

Abstract: This paper presents the results of groove and end face milling of CFRP materials by high speed steel end mill tools and polycrystalline diamond (PCD) and TiAlN-coated tungsten carbide end mill tools. The experimental results of end-face milling show carbon fibers on the surface of all the tools used in this experiment. However, the carbon fibers do not occur in groove milling when using PCD coated tools. In addition, the distribution of the carbon fibers of CFRP composites changed with the cutting temperature and cutting force. The overall result shows PCD-coated tools have longer tool life compared to high speed steel and TiAlN-coated end mill tools in processing carbon reinforced plastic composites.

Abstract: This paper describes the cutting characteristics of aluminum alloys in dry end milling experimentally. The tested materials are A1050, A2017, A2024, A5025 and A7075. The cutter is a flat end mill of Co-cemented High Speed Steel with the diameter of 20 mm. Through the experimental results of side milling, the following three aspects have been found out. Firstly, as to the machining error, A1050 showed smaller machining error than 15 μm in the cutting speed rage from 62.8 m/min to 251.3 m/min. Other Aluminum alloys showed greater values. Secondly, as to the cutting force, those of aluminum alloys except A2017 were generally proportional to their material hardness. The cutting forces of A1050 and A5052 were constant over the whole range of cutting speed. Thirdly, as to the machined surface roughness, A7075 showed the smallest surface roughness among the all materials with its arithmetical mean roughness Ra under 0. 2 µm and with its maximum height of profile Rz under 1 μm. The machined surface roughness of A2017 varied widely. Through the visual inspection of machined surface, A2017 and A2024 showed picked surface as generated by a built-up edge. This document explains and demonstrates how to prepare your camera-ready manuscript for Trans Tech Publications. The best is to read these instructions and follow the outline of this text. The text area for your manuscript must be 17 cm wide and 25 cm high (6.7 and 9.8 inches, resp.). Do not place any text outside this area. Use good quality, white paper of approximately 21 x 29 cm or 8 x 11 inches (please do not change the document setting from A4 to letter). Your manuscript will be reduced by approximately 20% by the publisher. Please keep this in mind when designing your figures and tables etc.

Abstract: The mathematic model was established between finished surface residual stress and milling parameters by orthogonal regression testing. The rationality of the model was certified by FEM and test. The simulation hypothesis and process were verified by the model. The test showed that the model and FEM were feasible.

Abstract: Gloss evaluation of a metal surface is important for the quality as the product. In general, gloss of a metal surface is influenced by specular reflection of light on the surface. Therefore to evaluate the specular reflection is almost the same as the evaluation of the gloss. We propose the method to evaluate the specular reflection using patterned area illumination. In the specular reflection, the angle of incidence is equal to the angle of reflection. Consequently when lights (rays) of the area illumination which has a stripe pattern are projected to a glossy metal surface, the stripe pattern occurs on the reflection image by the mirror-like reflection and the sharpness of the stripe pattern of the image has information of the specular reflection on the surface. This character is applied for the metal surface with hairline. The metal surface with hairline has different gloss feeling at different point of view. When the direction of the stripe pattern of the illumination is changed, the sharpness of stripe pattern on the reflection image varies owing to the surface roughness of hairline. Therefore we can evaluate the glossiness for various directions by rotating the stripe pattern. This paper shows the availability of the proposed method through the experiment.

Abstract: The machining of titanium alloys classified as difficult machining materials. It is a major problem how to improve the machining efficiency of titanium alloys. The TC4 and YS8 natural thermocouple pair was calibrated and the variation of electromotive force with change of temperature was obtained. The calibrated results were used to measure the cutting temperature while machining TC4 and the variation regulation of cutting temperature with cutting speed was obtained.