Papers by Keyword: Cutting

Abstract: Innovative developments of hollow cellular mat for lightweight structure must satisfy sustainability, fit for purpose and optimize design concepts. However, such materials necessitate appropriate cutting technology to allow trimming and shaping operations to be easily carried out on an excessive porous and perhaps non uniformity nature. This paper presents a work that aims at studying the machinability of porous cellular mat using a newly innovative cutting technology. A large structure of vertical bandsaw has been fabricated to cut the product with the size of 1m (width) x 1m (height) x 1m (long). The systems also equipped with a feeding table and strong structure frame to avoid product shifting during the cutting operation. The surface integrity showed minimum deformation with uniformed direction of surface removal marks. The cutting technology developed in this study is suitable for the hollow cellular mat for its simple trimming and shaping process and fine surface profile.

Abstract: Nowadays, lightweight design is a relevant issue in the automotive industry and in the field of electric mobility. The utilization of Press Hardened Components (PHC) made of manganese-boric steels enable weight saving through the reduction of the sheet metal thickness with sufficient component reliability. Because of the hard martensitic structure, by default, laser cutting is applied for piercing and trimming the contour after the Press Hardening Process (PHP). Due to the high energy consumption, in combination with long cycle times, this process is cost intensive.Instead of laser technology, shear cutting would be an interesting alternative for Press Hardened Steels (PHS) but this process poses substantial challenges for the industrial application. In order to cope with the difficulties of shear cutting operations of PHS, this work presents an alternative for processing PHS. This new method is called notch shear cutting.

Abstract: This paper deals with non-trivial problem aspects of laser cutting tool path generation that, to the best of our knowledge, received relatively little attention in the scientific literature. It is shown that some aspects such as plate edge nesting, skeleton and remnant cutting, and clamp positioning can be modeled and solved with little additional effort using existing tool path algorithms. However, concepts such as collision avoidance, pre-cut optimization, and bridge utilization prove to be more challenging and will require more profound algorithmic adjustments if these have to be taken into account fully. An even harder problem aspect is generating tool paths that are thermally feasible. Since laser cutting introduces net heat into the metal sheet, the metal sheet tends to heat up as the cutting progresses. Quality deterioration can occur if the laser spends too much time cutting in the same region. It is shown how to model the easy problem extensions in order to handle them using existing problem approaches and solution approaches are suggested to tackle the harder concepts. In addition, a proof of concept is presented that shows that thermal feasible tool paths can be generated through a multi-start heuristic utilizing a thermal penalty function. A finite difference method iteratively (or concurrently dependent on the used heuristic) evaluates the thermal feasibility and updates the penalty function.

Abstract: The flow zone of the chip in contact with the tool reaches a high temperature in cutting. According to chip hardening experiments α-γ transformation may occur in steel, so the tool is in contact with a high-temperature γ phase at high pressure. The microscopic examination of worn surfaces showed that the degradation of the tool is the result of adhesive/abrasive and thermally activated processes, therefore both friction length and temperature must be taken into consideration in the modelling of crater wear. Wear rate can be described by a non-linear autonomous equation. TiN coating, which increases tool life in high speed steel, changes and slows down the wear of the tool. The activation energy of wear can be calculated from the constants of the wear equation determined by cutting experiments. The deoxidation products to be found in the workpiece in cutting may form a protective layer on the TiN layer that blocks or slows down wear.

Abstract: Tread rubber is formed with two purposes. A separate wire beneath the tread rubber powder processing to reduce tool wear Dayton speed , and the other is to reduce tire division cutting the number of large particles of plastic blocks to shorten the grinding process . Tread rubber processing is in the tread ring body segmentation . Ring with the tread surface of the body as clamping plane. Clamping the tread ring body is an elastic expansion of the clamping piece . Processing machinery designed modular form while completing the tread rubber strip on the mouth of cutting and peeling colloids . In front of the tool cutting point increase in the formation pressure roller is smooth plastic surface processing point . Limiting processing to control the separation of the tread rubber tread rubber particles.

Abstract: In view of the field work environment of artificial larch forest in the mountains, The forest seed Loam cutting and collecting machine is designed for adapting to the mountain woodland inter-row work environment. The machine finishes completing the soil cutting and collecting through a homework, meeting the job requirements, and the operation is simple、the ability is strong, it can meet the need of mountain forest farm.

Abstract: Surface texturing has become a technique to reduce friction and wear in cutting process; laser surface texturing is a method used to create micro-dimples on the interface surface. It is considered that cutting of titanium is difficult. As the experiments are costly and time demanding, metal cutting modeling provides an alternative way for better understanding of machining processes under different cutting conditions. In this paper a 3D finite element model has been used to simulate the cutting process of titanium alloy Ti6Al4V to predict the cutting forces and temperatures.

Abstract: In the laboratory of cutting machining technologies from the “Gheorghe Asachi” Technical University of Iaşi, a series of investigations on the machinability of cast iron samples having various structures were designed and developed. The aim of the research was to know and to explain the way in which various constituents of some iron castings exert influence on the degree of wear of a milling tool made of high speed steel. Within this research, mathematical empirical models were determined, in order to calculate the cutting speed v₆₀, considered as an indicator for the evaluation of machinability. The research allowed establishing the factors able to have a major influence on tool wear phenomenon and obtaining thus a more complete image concerning the machinability of grey iron used for castings.

Abstract: The paper treats the analysis of losses of juice/material resulting from shredding of food materials with soft texture by means of metal wire cutting. For a better relevance of determinations have been chosen different food materials, different diameters of metal wire cutting and different heating temperatures. The objective of this analysis is to identify the correlations that exist between the cutting device and the product obtained after shredding, in order to improve shredding efficiency by reducing the losses of juice / materials resulted from shredding of food materials.

Abstract: In the production process of sheet metal parts, oil is widely used as lubricant, not only in sheet metal forming but also in shearing and blanking. Due to environment, health and cost reasons, the absence of lubricants is an aim for future production as it has initiated for machining in the last years. For lubricant-free shearing, it has to be known if there is an influence on the process itself when using oil or not. To find this out, experiments are carried out with a small testing device installed in a tensile testing machine and a blanking tool installed in a servo press. With the small device it is possible to make a piercing process with a circle punch of 16 mm diameter. The blanking tool produces a larger cut part with different holes and open cuts. Without lubricant, there is no difference in the maximum shearing force for the small device while the stripping force is higher and the cut edge zones differs slightly. Using oil or not has a small effect on the force using the blanking tool.