Advanced Materials Research Vols. 941-944

Abstract: There are many kinds of expanding mould, and rubber punch is more than others. Of course there are many hydraulic pressure mould, but there are a litter of which can be multipurpose and be suit for many kinds of products. Through researching some kinds of products, using of a kind of called Half structure and a common use of die set, a kind of no punch hollow part hydraulic pressure expand mould was designed. In this kind of mould, the product can be separated from the mould and be reset easily, and only the cavity size should be designed because of the outer size of mould never be designed. It has a fixed size and structure. The punch was made of rubber capsule, when product was needed to expand, the hydraulic pressure oil was supplied by the oil pump. When the product was needed separated from the mould, the oil in rubber capsule should be taken out of it at first, then the Half structure may be ejected, at the return trip, a T shaped pole was used to reset. This mould was of simple in structure, and the action was reliable and very practical.

Abstract: This paper regard the development for bush type bear metal using centrifugal casting by changing the rpm, amount of melting metal bush type bearing metal process was fixed also bush type bearing casting is possible by using centrifugal casting machine, bonding test results meet the specification and results of non-destructive testing meet the inspection.

Abstract: Transportation always plays a significant role in national economy, of which roads and bridges are the most important facilities. The conditions of the road surface have an overwhelming influence on the traffic flow and road safety, especially in winter and the regions with frequent snowfall, thus closely affected the development of the urbanization and economic prosperity. In view of this, this article has analyzed the characteristics of the existed de-icing technologies, coming up with a new synthetically de-icing method which consists of thermal water-jet cutting with mechanical milling technology. These two kinds of de-icing methods are combined as a set of multi-functional system, in which the thermal water-jet cuts the ice layer into separated sections, and the mechanical milling unit then easily removes the remaining sections out of the road. To obtain the prime influential factors in this new de-icing device, repeated indoor experiments were conducted, which provides some theoretical references to further advance the de-icing efficiency and make structural optimization.

Abstract: In this paper, the oxide nanometer composite cutting performance of ceramic tools cutting cast iron were studied. And the tool failure modes were mainly analyzed. Through the study found that, with the increase of tool wear with cutting speed, failure forms mainly adhesion wear. When the cutting speed is low, the knife before the crater wear become the main form of ceramic cutting tool wear, boundary wear and the surface of the knife after wear is also very serious. And in the process of cutting, the collapse edge can also occur now; With the increase of cutting speed, collapse become the main failure forms of cutter blade.

Abstract: The mechanism of surface cracks penetration testing are studied, as well as, the cracks’ width and depth of penetration testing formulas are given in the paper, which provide the basis for TC4 titanium alloy structure's penetration testing. The process of fluorescent penetrating testing is analyzed, and the result that detection experiments of TC4 titanium alloy structure's surface crack indicating the changes in the curvature is larger the structure is easier to produce surface cracks. The reason that the surface cracks of structure of TC4 titanium alloy is theoretical analyzed and experimental studied. In process of machining TC4 titanium, cutting parameters are important factors causing stress concentration, particularly, the larger cutting depth will generate surface cracks.

Abstract: To predict the machining results of ultrasonic vibration grinding assisted electric discharge machining (UVGAEDM) in the condition of building predictive model with a few samples but fluctuant values, a predictive model based on SVM was proposed in this paper. Taking machining SiCp/Al as an example, the samples for modeling were obtained through orthogonal test, and then the predictive model was established utilizing MATLAB. Finally, the model was optimized to further improve the prediction accuracy about the processing indicatorssurface roughness and processing velocity. It shows that the predictive results are in good accord with the test results, with the maximum relative error being less than 12%, meaning the predictive model is reliable and effective.

Abstract: For joining and cutting non-woven fabrics, an ultrasonic wide-blade horn is expected to be used effectively. During the joining and cutting process, this horn can work as the punch in the punching and blanking systems. The performance of a wide-blade horn is normally relevant to the resonance at the operating frequency, the vibration amplitude, and the uniformity of the amplitude on the output surface. In this study, an ultrasonic wide-blade horn is optimally designed and fabricated for joining and cutting non-woven fabrics, and it is tuned to operate at 20 kHz, the resonant frequency of the converter. Analytic and experimental results show that based on the modal and harmonic response analysis and repeated tuning, the wide-blade horn could be optimally designed and fabricated. The resonant frequency of the developed horn was 19,979 Hz, and the amplitude uniformity of the output surface was 76%.

Abstract: Thin-walled workpiece is easy to deform in machining. In order to predict the dimensional error of machined surface of thin-walled workpiece, computer simulation technology is studied, which is called virtual machining process. For the simulation of workpiece deformation, much numerical analysis should be done. Research indicates using FEA (Finite Element Analysis) in each step of simulation process needs too much time to meet the requirements of industrial application. Therefore it is important to decrease the simulation time. In this paper, a new method is proposed to realize rapid analysis of workpiece deflection in virtual machining process, which combines rapid analytical solution method with a few times of accurate FEA, thus greatly decreases the time required for whole simulation. For the simulation, several peripheral milling process models are presented with increasing order of sophistication and accuracy, which can be applied to simulate cutting process with the effect of workpiece deformation caused by cutting force. In the final section, the comparison between simulation results and experiments shows the proposed methods and models can closely predict dimensional error and texture of machined surface of flexible workpiece.

Abstract: The main aim of this contribution was monitoring of chip in the milling process by the evaluation of the volumetric coefficient of chip. The chip was monitoring during the peripheral up and down milling. Nowadays, the milling is the most used technology in engineering. The shape of chip is important for its transport and for economical aspect of this technology. This coefficient represents the shape of chip. The small chip has a lower volumetric coefficient, but the very small chip is not very desired in the cutting process, because they can fill some small spaces and damage the machine. But very long chip can damage tool and machine, too.

Abstract: Shear angle and friction angle are the two characteristic parameters in orthogonal cutting model. This paper investigated effects of feed per tooth on shear angle and friction angle in orthogonal milling of titanium alloy Ti6Al4V by experimental approach. Three different straight tooth milling tool with different rake angles are used in this research. Experimental results reveals that in orthogonal milling of Ti6Al4V alloy, shear angle will decrease with increase of feed per tooth and friction angle will increase with increase of feed per tooth. And then variation of shear angle and friction angle affect the values of force coefficients. The experimental results provide deep understand of basic physical phenomenon in milling process and sheds light on more accurate cutting force modeling.