Applied Mechanics and Materials Vol. 459

Abstract: The content of this article also focuses on the analysis of the tool life of screw drills. This paper presents the conclusions of tests on a stainless steel DIN 1.4301.The results of the article are conclusions for working theory and practice for drilling of stainless steels. Based on the cutting tests, cutting speeds of 30 to 60 m/min, feed rate of 0.04to0.1 mm and screw drill carbide monolite.

Abstract: The basic hypothesis of this article focuses on the study changes in deformation under the machined surface of stainless steels and steel C45 when drilling. The problem of drilling holes with diameter D=5 to 12.5 mm resides in the fact that 25 to 30% of these holes do not comply with prescribed requested requirements. This article presents the results of experiments focusing on the study of the damage process in helical drills with diameter d=8.0 mm when drilling into austenitic stainless steel DIN 1.4301 and steel C45. This study also includes an analysis of accompanying phenomena in the cutting zone by measuring some selected parameters.

Abstract: The push-through bending process can be regarded as a bending mechanism with two fixed diepoints and two movable diepoints, resulting in a total of four points. It can also be regarded as acontinuous four-points bending. As compared to other bending processes, there is severe friction at the contact area betweenthematerial and die in push-through bending. In this paper, we clarify different aspects of lubrication and research excellent lubrication oil in push-through bending. Based on theresultsobtained, it was found that adhesion occursdepending on the lubricant used and the occurring force. It was also confirmed, that olefin is effective as a remedy for oiliness, in case of using a mineral oil-based lubricant. In addition, it was confirmed that excellent lubrication oil could be obtained by increasing the alcohol content and adjusting the content of synthetic ester. This is a good alternative to the more expensive olefin.

Abstract: In our previous study, we reduced the slide marks on material surfaces by optimizing the lubricant for push-through bending. In this study, we investigate contact conditions of material deformation in dies during push-through bending. We also attempt to reduce slide marks by investigating the die material, die surface treatment of the die, and roller die set and to clarify the following. Bending deformation and flange wrinkling occur in fixed dies during push-through bending. Sliding between the material and the die begins inside the fixed die. A cemented carbide die is excellent for obtaining ideal surface roughness of the slide marks. Hard metal dies tend to have excellent sliding characteristics. Cold die steel (SKD11) and high-speed steel (SKH51) have almost equal hardness, and their qualities exist harmoniously between the bending member and the die material without the above relationship. When we treat the die surface or use the above dies, roughness of slide marks increases. The die-surface roughnesses in Diamond-Like Carbon (DLC) processing and Toyota Diffusion Coating Process (TD) are minimal, and the surfaces of their bending members are smooth. Furthermore, their efficiency is nearly equal to that of cemented carbide dies without surface treatment. Using a roller die effectively reduces slide marks. However, a roller die contacts the bending member locally, and the contact pressure is higher than with a normal die. Thus, a roller die is inferior to a normal die in its curvature, deformation, and flange wrinkling. The structure of the roller die is most suitable for parts with small curvatures.

Abstract: In this paper, a solid, single link soft robot finger was modeled with SILASTIC P-1 Silicone, supplied by Dow Corning^®. The material is anon-linear hyper elastic, strain dependent, room temperature vulcanized (RTV) rubber. When the fingers are actuated for grasping and object manipulation, they vibrate with excessive amplitudes, which will disturb the precise positioning of the fingers. Vibration analysis through numerical simulation was conducted in ANSYS^® V12. The first ten fundamental frequencies and their mode shapes were numerically computed and presented from modal analysis. The lowest natural frequency of the finger model was found to be 2.14 Hz. The dynamic stiffness of the finger model was then computed from the natural frequencies. It was found to be nonlinear in nature. The dynamic characteristics of the finger model during the excitation between 1 Hz and 1000 Hz were studied in transient analysis. The peak acceleration occurred at 9.3 Hz, while the peak velocity occurs at 3.75 Hz and 4.8 Hz with the magnitude of 0.013 mm/s.

Abstract: In recent several years, although production of magnesium has risen dramatically, production of magnesium alloy sheet remains still at a very low level in practical use. The major barrier to greatly increased magnesium alloy use has been in still primarily high manufacturing cost as well as poor work ability of wrought magnesium sheet alloys. One of the author has investigated in cold roll forming of magnesium alloy, however detailed forming characteristics of the wrought magnesium alloy sheets has not been clarified. The aim of the study is to confirm possibilities of practical use of wrought magnesium alloy by using told roll forming process. A three dimensional elasto-plastic analysis by finite element method (FEM) has been conducted to examine the shapes of cross section, spring back characteristics, bending strains and longitudinal membrane strain of magnesium alloy sheet and cold rolled steel sheet during forming.

Abstract: With the globalization of economic development, the competition between the enterprises becomes more intense. If you want to have a survival advantage in the fierce competition, you must find ways to achieve high efficiency and low cost strategy. But simply to raise revenue or simply to cut costs can't satisfy the requirement of enterprise survival and development. Therefore, to increase income and reduce cost, the combination of both, become the first background of enterprise development. The concept of supply chain cost management meets the requirement of this strategy. Diversity of the concept of supply chain, and constant adjustment along with the market determines the supply chain cost management is comprehensive and complicated system engineering.

Abstract: Based on the size of casting surface parts and the product quality, expendable pattern casting as a new casting method, it greatly improve production efficiency and save the manpower. With the cast process of mixing arm, as the study objective. It can preliminary identify the process plan by analysis of structure of workpiece surface and the casting process. It obtained the registered product under the considering of the main parameters and the rough size. The researched results can supply the reference value for the design and research of the expendable pattern casting.

Abstract: In order to ensure maximum effectiveness of wind turbines, the cabin must be accurate to the wind, only wind turbine impeller in the normal direction and the wind direction is agreed upon, to ensure that the wind turbine power absorption maximum, to ensure the normal operation of fan safety and full use of wind resources. Therefore, the wind vane and anemometer in the wind turbine system plays an important role, this study focused on the gold 1.5MW wind turbine with wind vane and anemometer common fault..

Abstract: This article proposes a stochastic collocation method to investigate the uncertainty quantification in fatigue damage prognosis where experimental data are limited and only interval bounds on uncertain parameters are given. The method derived from tensor-products or sparse grids consists in a Galerkin approximation in random space, requires the use of structured collocation point sets and naturally leads to the solution of uncoupled deterministic problems as in the Monte Carlo approach. The distribution of remaining useful life can be acquired by dividing each interval into several small parts and assuming the corresponding random variable obeys uniform distribution in the small range. Compared with Monte Carlo method and interval arithmetic, this approach is much more efficient, time-saving and gets more accurate predictions. An experimental investigation of fatigue life prediction of a metallic plate with a central crack is presented to demonstrate the efficiency and effectiveness of the proposed method.