The Fininte Element Simulation Of The Deformation Processes Of Titanium Ring Pipe

The pure titanium seamless ring pipe (SRP) is a kind of important components widely used in astronaut, voyage and automobile industries. It has potential for gas bottle due to its small volume, light weight and bearing high pressure. The uniformity in the thickness of SRP will directly affect the requirement of its high pressure resistance and strength homogeneity, furthermore, the quality of the whole system. Thus the processing technology is of great significance.In the thesis, the combination of experiment with computer numerical simulation is introduced to systematically research the process of the diameter-pushing heat expending technology of the commercial pure titanium TA2 ring pipe using MSC/Autoforge simulation software. The main results are as follows:1. The Archimedes line is introduced in this paper as the center axes of the pushing processing die, which will reduce the deformation and be prone to the metal flow uniformity from concave to convexity, which can identify the aim of wall thickness uniformity, which can eliminate increase of inner wall thickness and decrease of outer wall thickness in the deformation of pipe bending.2. The Archimedes constant α is the key to die design and the premise of wall thickness uniformity. The smaller α , the easier pushing, but the thinner wall thickness;the bigger Archimedes modulus α , the more prone to wall thickness uniformity, but the easier crinkling. The optimization of Archimedes modulus α is also 1.0.3. The bigger expanding diameter ratio K, the thinner thickness and the bigger thickness tolerance;the smaller expanding diameter ratio K , the thicker wall thickness, the bigger thickness tolerance yet, easier crinkling. Fit K can balance of action of expending diameter and action of bending. The expanding diameter ratio is also 1.3.4. The smaller pushing velocity V , the thinner inner wall thickness;With the V increasing, inner wall thickness will also increase gradually, but given the bigger than 4.0mm/s V , pipe bending is prone to crinkling, its wall thickness tolerance will increasing. The optimization V rang is also 3.5mm/s.5. The best pushing temperature is (750° C-8OO0 C). The temperature of pipe bending away from die is not smaller than 600° C, Or it will make pushing fail.Above of all, optimization parameters mandril die design are as follows: a =1.0 and K= 1.3;the parameters of technics are as follows: the temperature range of 750-800°C and V= 3.5mm/s.