NAS (National Aerospace Standard) 979 is the only standard well known in industry describing a five-axis machining test for measuring kinematic errors of five-axis machine tools. As it cannot reflect the tool path characteristics of typical ruled surface machining, five-axis machine tools which passed the NAS test may not have the ability to satisfy the requirement of the real industrial applications. To fill this gap between the NAS test and the real industrial applications, an “S” machining test is proposed in this paper. The case study shows that the proposed machining test is feasible and practicable.

Titanium alloy is finding increased application in aeronautical, automobile and structural applications. During post processing of titanium alloy, milling is one of the mostly used machining processes. In this study, the relationship between temperature and milling parameters was developed by response surface methodology (RSM), and a temperature model for milling titanium alloy is proposed. The model is found to be adequate through ANOVA. The result indicates that the increase in cutting speed and feed rate increases the temperature. The radial depth of cut and depth of cut do not show a general trend on temperature in milling of titanium alloy.

Multi-axis CNC machining shows great advantages in manufacturing parts with geometries being defined by complex surfaces. NURBS (Non-Uniform Rational B-Spline) interpolation and polynomial interpolation are two new types of interpolation to improve productivity. Compared to the NURBS interpolation, the polynomial interpolation can gain higher productivity. However, no commercial software tool is available to generate polynomial interpolation CNC programs. This paper proposes a postprocessor to generate polynomial interpolation multi-axis CNC program. A case study with simulations demonstrated that the polynomial interpolation program generated by the proposed postprocessor has higher machining efficiency than liner interpolation and NURBS interpolation program.

Pockets are widely applied in the design of the aircraft structural parts. For achieving aggressive weight targets, pockets are always designed by thin walls and webs. When machining a pocket, the web is created at the face of the end mill, as opposed to ribs, which are created at the periphery of the end mill. However, difficulty exists for control the thickness tolerance when machining these thin-webs. In this paper, the on the machine measurement technology is adopted to help control the thickness accuracy of thin webs. A typical part is taken to illustrate the proposed method and test results show that the proposed method efficiently improves the machining accuracy of thin webs.