The objective of this paper is to analyze the precision of plastic parts made by using robot milling. Currently, the robots have good precision, rigidity, flexibility and they are able to machine parts. By using a six axis Kuka robot and an electric spindle, a plastic part was milled. The paper presents the advantages and disadvantages of this new technology, analyzing the dimensional accuracy, surface quality and costs.

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Abstract. The paper presents an experimental study on processing composite materials using abrasive water jet cutting (AWJC) process, analysing one of the main process parameter, standoff distance (SOD). Carbon Fibre Reinforced Plastics (CFRP) are used in a wide range of industrial applications, like aerospace and automotive. Cutting CFRP using AWJC involves several challenges like high dimensional accuracy and good surface quality. To produce precise parts by using this process must be understand the influence of the process parameters on quality characteristics. On this study was investigated the standoff distance influence on kerf characteristics. The characteristics of the cut surface (kerf geometry, surface roughness and topography) were analyzed.

This paper presents the basic principle for achieving a custom implant from biocompatible materials with the human body using Additive Manufacturing technologies. Due the fact that is a new product which will be introduced on the market, a marketing study was needed. This study presents also the mathematical, analytical and graphical modeling of the psychological price, for a custom implant type cranioplasty / hip prosthesis / spinal implant. The assessment of psychological price for a custom cranioplasty implant, that is not the object through curative Romanian health programs, bring relevant information on the knowledge of maximum and minimum limits that the purchasers, potential consumers, are willing to accept, so the price at which the proportion of consumers potential is the greatest.

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Abstract. The paper presents a preliminary experimental study on processing composite materials (CFRP) using abrasive water jet cutting (AWJC) process, analysing the possibilities of occurrence of material delamination. AWJC is a proper solution for cutting CFRP because of reduced interface temperature, high flexibility, low mechanical loading and reduced cutting forces. Cutting CFRP using AWJC involves several challenges like material delamination due to the high velocity impact of the jet. To understand the delamination, three experimental tests were made: in the first test the cutting and the drilling was made with high water pressure (350 MPa), in the second test the cutting was made with high water pressure and for drilling was used low water pressure (200 MPa) and in last test a pre-drilled hole was used. Within those experiments was observed the CFRP delamination appears just during the drilling, not during the cutting. By decreasing the water jet pressure, the jet energy is decreased and in this way the delamination decrease.

The main objective of the paper consists in remanufacturing of a part, through Abrasive Water Jet Cutting, using a method of reverse engineering based on 3D scanning. The characteristics of this process, the equipment and the main applications are presented. The research starts with manufacturing of a master model made by CFRP. This master model is a complex part cut by abrasive water jet cutting. In scanning process was used the 3D Scanner Artec Space Spider and the point cloud was processed using Artec Studio 11 software. By using this new 3D model was manufactured a new part, with the same setup. The quality characteristics (accuracy and surface quality) of this part was compared with the master model. The paper presents the advantages and disadvantages of this reverse engineering method applied on abrasive water jet cutting process.

Carbon Fibre Reinforced Polymer (CFRP) is used in top industries like aerospace, automotive or medicine. Abrasive water jet (AWJ) technology has demonstrated its capacity in machining CFRP parts with a high dimensional accuracy due to its low mechanical loading, reduced machining temperature, high productivity, reduced tooling, and environmental friendliness. An important challenge when machining composite materials with AWJ is material delamination, determined by the high-speed water jet hitting the material during the piercing process. It is the ideal tool for cutting complex CFRP parts, in cases where the piercing point is outside of the workpiece. The challenge lies in machining features where material piercing is required, like holes, slots or internal contours. This paper presents a method of piercing the composite materials with abrasive water jet, that can avoid delamination. The method requires adding the abrasive particles in the water jet at the very beginning of jet formation, thus obtaining a mixed abrasive water jet during the first impact with the composite workpiece. A new cutting system was designed and set up based on the proposed piercing method and was compared with a conventional AWJ cutting system. The insertion of the abrasive particles into the water jet was monitored by using acoustic emission (AE). An analysis of the influence of piercing parameters (water pressure, standoff distance, abrasive inlet angle and abrasive delay time) on the delamination was conducted. The process outcomes such as hole surface integrity, delamination, particles embedment, uncut fibers and dimensional characteristics, were evaluated. The results show that the method is promising in reducing delamination.