Thermographic Monitoring of Laser Cutting Machine

Computer Numerical Controlled (CNC) laser cutting tools are developing as an alternative to conventional cutting systems thanks to increased accuracy, non-contact processing, higher productivity, less energy demand. An IR camera is utilized to monitor the laser cutting process of a steel plate. Even though the process is very complicated an analytical solution of the temperature field generated on a slab by a point source moving along one direction of the plate surface is provided in order to interpret the temperature field experimentally obtained by the IR camera.

Increased durability parts of tillage machines, adapted to soils of different types

Purpose. Justification of rational parameters of hardening of the working bodies of tillage machines by the method of electro arc processing. Methods. The experimental, mathematical and statistical, monographic. Results. The technology of local hardfacing, which improves the wear resistance of the surfaces of the parts of modification with the use of electro arc processing and with additional point hardfacing with the use of variations in processing modes, various technological methods and materials for adaptation to specific operating conditions. Conclusions 1.According to the results of theoretical studies, the heat balance of the process of electrical contact processing was determined, which allows to determine the most significant factors affecting the energy performance of the process, namely, the controlled voltage U of the arc process of electrical contact processing. 2.According to the results of experimental studies, rational values of the controlled voltage U in the process of electro arc processing within 35–55 V were established, which ensures surface roughness in the range from 0.4 to 1.0 mm. Keywords: electro arc processing, hardfacing, heat balance, parts of tillage machines, regimes, roughness, wear resistance.

Research on the Key Technology of Automatic Programming System for Line-Contact Processing

In view of the current situation of line contact efficiency of NC machining without automatic programing system, the automatic programming system for NC machining based on line contact processing is developed. According to the characteristics of line contact processing, the key technologies in the automatic programming system of this paper is studied. After surface modeling, the data of DXF files generated by CAD systems can be read. And the surface processing information is obtained by these data sorted. Through the design of machining process and the sorting of tool path, the tool path of line contact processing is got. Then the research of soft cut of ruled surface is completed, and the graphical automatic programming is realized.

Advanced metrology of Laser Groove Buried Contact processing for silicon CPV

ABSTRACTThe solar cells employed in low to medium (50 to 200 suns) concentration photovoltaic (CPV) are usually mono-crystalline silicon. Laser Groove Buried Contacts (LGBC) are preferred to screen printing in these cells due to the high currents generated in the system. In this paper, we report on the use of Coherence Correlation Interferometry (CCI) to accurately measure the width and depth of the laser-ablated grooves. In addition, the technique is also used to measure the surface roughness at the bottom of the trenches, since this can determine the success of the subsequent plating process, and at the top surface to optimize the debris control and obtain clean surfaces and well-shaped groove edges. The laser ablation process was also optimized to obtain the groove aspect ratio and surface quality required. Process parameters to be controlled include laser power, pulse energy, stage speed and focal length. The CCI technique is capable of providing all the groove and surface metrology required for this process optimization.