The anisotropic, heterogeneous and coarse granular structures of austenitic stainless steel welds lead to important disturbances of the ultrasonic propagation: beam skewing and splitting, attenuation, backscattering and spurious echoes. These disturbances have been studied by EDF R&D for a few years in order to improve the ultrasonic NDT in nuclear applications. In particular, a methodology for...

Abstract –Demands of micro aspheric optical components such as lenses and mirrors are increasing for installing to the digital devices such as DVD, Digital camera, mobile phone and virtual reality system. As the devices become to be more compact and complicated, the molds shapes of lens and mirrors would become smaller and complicated, and then would become more difficult to be machined and mea...

This paper is an endeavour to critically appraise the existing methods used for real-time simulation of machine tool dynamics with the emphasis on modelling and simulation of the dynamic behaviour of CNC machine tool feed drives and mechatronic systems for machine tools. The actual approaches for linking the feed drive models with structural models for CNC machine tools are examined. Also the f...

A virtual machine tool (VMT) is presented in this two-part paper. In Part 1, the analytical foundation for a virtual machining system is developed, which is envisioned as the foundation for a comprehensive simulation environment capable of predicting the outcome of cutting processes. The VMT system undergoes “pseudo-real machining”, before actual cutting with a CNC machine tool takes place, to ...

Ultrasonic-assisted inner diameter machining is a slicing method for hard and brittle materials. During this process, the sawing force main factor affecting workpiece surface quality tool life. Therefore, based on indentation fracture mechanics, theoretical model of cutting an ultrasound-assisted saw established in paper improvement. The experiment was carried out with alumina ceramics (99%) as...

Titanium alloys are widely used in aerospace, the military industry, electronics, automotive fields, etc., due to their excellent properties such as low density, high strength, high-temperature resistance, and corrosion resistance. Many components need be finished precisely after being cut these applications. In order achieve high-quality high-efficiency finishing of titanium alloys, ultrasonic...

A new horn for high displacement amplification is developed. The profile of the horn is a cubic Bézier curve. The ultrasonic actuation of the horn exploits the first longitudinal displacement mode of the horn. A design method of the horn using an optimization scheme and finite element analyses is developed. Prototypes of the horns are manufactured by a numerical control machining process. Perfo...

Ultrasonic assisted drilling (UAD) has been reported effective for thrust force reduction during drilling of CFRP resulting in lower exit delamination. However, this process is not fully understood in relation to machining theory. This work focused on understanding the separate effects of chisel and cutting edges during UAD in comparison with conventional drilling (CD). Experiments were perform...

the applications of electrochemical machining are increasing because of increasing requests of industries for materials with high strengh and high hardness. regular ecm uses a tool with spicified profile shape that is similar to final shape of workpiece. in this reasearch a nozzle that delivers electrolyte to the machining gap is used for machining cylinderical workpieces. by moving the electro...

This paper presents the Optimization of Non-Traditional Machining (NTM) process for the Electrochemical Machining Process by Particle Swarm Optimization Technique. The main aim of the work is to find the optimum values of machining parameters. The NonTraditional or Unconventional Machining Process has proved to be better than conventional machining process to a large extent. Keywords—Convention...