Effect of pulsed laser treatment on the structure of alloyed cast iron

In the process of operation friction parts of mechanisms are subjected to significant wear. The wear resistance of such parts can be increased by carburizing, nitriding, plasma treatment, and other methods. Surface strengthening can be provided by laser treatment, which in some cases is more favorable technologically. The present work concerns the possibility of laser strengthening of the functional surface of shaft cams for ZAZ-1102 (Tavria) automobiles. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 4, pp. 11–13, April, 1997.     

Optimal cutting condition determination for milling thin-walled details

This paper presents an approach for determining the optimal cutting condition for milling thin-walled elements with complex shapes. The approach is based on the interaction between the thin-walled detail and its periodic excitation by tooth passing, taking into account the high intermittency of such a process. The influence of the excitation frequency on the amplitude of the detail oscillation during milling was determined by simulation and experiments. It was found that the analytical results agreed with experimental data. The position of the detail when the tooth starts to cut was evaluated through experiments. The influence of this parameter on the processing state is presented herein. The processing stability is investigated and compared with the proposed approach. Thereafter, spectral analyses are conducted to determine the contribution of the vibrating frequencies to the detail behavior during processing.The full text can be downloaded at https://link.springer.com/content/pdf/10.1007%2Fs40436-018-0224-y.pdf     

Calculation Method for Analyzing the Vibration Resistance for Thin-Walled Elements

Strength of Materials - When employing end milling for the thin-walled elements, in particular aircraft gas-turbine engines, it is possible to observe their forced vibrations due to the machining...     

Vibration Diagnostics of a Damaged Inclined Cylindrical Shell

Free vibrations of an inclined cylindrical shell with a breathing crack are analyzed by the authors in view of the results of spectral diagnostics of transverse vibrations of a beam with a closing crack, which were obtained by A. A. Matveev and A. P. Bovsunovskii at the Institute of Problems of Strength of the National Academy of Sciences of Ukraine. Elastic characteristics of the shell are interpreted as a certain bilinear system. Data on the stiffness degradation due to the crack opening can be used for the selection of vibration damage indicators. We have obtained relationships between the relative stiffness degradation, crack depth, and crack location. It is demonstrated that the potential energy of tension of the shell median surface must be taken into account. We have found that the efficiency of detecting damages using vibration diagnostic methods improves with increasing shell thickness.