![]() In each series, four crystallization processes were carried out at four different withdrawal rates: 2, 3, 4 and 5 mm/min. The directional crystallization with the use of a spiral selector (S, Figure 1a) and heat treatment process was performed in the Research and Development Laboratory for Aerospace Materials at the Rzeszów University of Technology, Rzeszów, Poland using industrial ALD Vacuum Technologies furnaces. Each series consisted of four blades obtained at different withdrawal rates. ![]() The as-cast blades made of CMSX-4 Ni-based superalloy were heat treated and then analyzed. ![]() The Bridgman technique was used for production of two series of single-crystalline turbine rotor blades. and were referred to as the deflection of dendrites on the mold surfaces. These mechanisms of dendrite interaction with the mold walls were proposed for the first time in Refs. In the former case, these boundaries may be formed after heat treatment, for example through the process of dislocation polygonization, while in the latter case the boundaries may be formed directly during crystallization. Both mechanisms can lead to the formation of low-angle boundaries. In both cases, further growth of a dendrite takes place due to the secondary arms that are perpendicular to the primary arms. The higher angles prevent a further growth of the primary dendrite arms without a change in the growth direction. For lower angles, the dendrite primary arms may slightly change their growth direction near the surface, thereby creating areas of internal stress, and then stop. The character of interactions may depend on the angle between the axis of the dendrite primary arms and the mold surface. Additionally, the inclination of the airfoil surfaces in relation to the Z axis of the rotor blade makes the growing dendrites contact the mold walls and interact with them. Therefore, even if the mold walls are parallel to the Z, this means the dendrites can contact them. ĭuring directional crystallization, the dendrites grow directly toward the -type direction, which is only close to the blade axis Z. Due to similarity between the structure of both phases and the possibility of obtaining a clear X-ray diffraction pattern, the blades can be recognized as single-crystalline blades. ![]() The dendrites and interdendritic areas that are formed during the Bridgman process mainly consist of the Ni-based γ primary solid solution and the Ni 3Al-based γ’ secondary solid solution. The blades are obtained through directional crystallization using the temperature and withdrawal parameters that allow the formation of an array of dendrites nearly parallel to the blade axis, with the crystal orientation of each dendrite being parallel to the axis. The single-crystalline rotor turbine blades, which have a very complex shape, are usually produced by using the Bridgman technique. The single-crystalline parts made using the CMSX-4 superalloy possess high strength properties, even at high temperatures, which is especially important for turbine rotor blades, as these types of blades are exposed to harsh working conditions. Treamyx.The turbine components of aircraft engines are currently most often produced using the CMSX-4 superalloy. Venture- Soldar Engineering & Construction. Malaysia and SE Asia region.With great list, comes great power. LIST OF NDT COMPANY AND EMAILS(2010-2012 UPDATE)The ultimate ![]()
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