using molybdenum cutting wire
The large number of large-thickness parts put forward higher requirements for molybdenum wire -cut electric discharge machining. General high-speed thread cutting machine is only suitable for processing workpieces with a thickness of 100mm or less. When the workpiece thickness exceeds 100mm, the processing stability is degraded, and the machining accuracy and surface roughness cannot meet the processing requirements, and the processing is difficult. In order to meet the requirements of production and manufacturing, it is necessary to thoroughly study the technological rules of cutting and processing of large-thickness workpiece lines, improve the processing stability, and improve the technological effects. However, it is very difficult to study large-thickness molybdenum wire -cutting using traditional processing methods. This is not only limited by the structure of the machine tool, but with the increase in the thickness of the workpiece, it is difficult for the working fluid to enter the kerf, making it difficult to discharge the galvanic corrosion products in the kerf and accumulate in the kerf.
The accumulation of electrolytic products reduces the flow of the working fluid. The electrode wire is not cooled and the electrode filaments are burned, which interrupts the process and makes it difficult to perform a large thickness cutting test. Therefore, for large thickness molybdenum wire cutting, it is difficult to carry out systematic process tests to study its processing mechanism. Simulating the molybdenum cutting wire -cutting process of large-thickness workpieces on a wire-cut electric discharge machining simulation system, only virtual machining is performed on a computer. It is not limited by many factors in the actual processing and can be used in processes that are difficult to carry out in actual machining experiments, and can get the simulation results.
Through the analysis of the simulation results, a method for solving the chip-removal problem of large-thickness line cutting processing was obtained, and verified from both the theoretical analysis and the process test.
When large-thickness molybdenum wire -cutting is performed, the arrival of liquid into the kerf is small, and chip evacuation is a major problem. During the processing, we found that the pulse parameters have a significant effect on the line cutting process of large thickness workpieces. The value of the pulse parameter determines the discharge energy, discharge frequency, and discharge gap state. Its reasonability depends on whether the discharge machining is stable or not. Therefore, the effect of three main pulse parameters (pulse peak current i., pulse width t. and pulse interval t.) on the machining process is studied through simulation.
Shanghai Jiaotong University independently developed high speed molybdenum wire cutting
Process Effect Simulation System for DK7725 High Speed molybdenum wire Cutting Machine
The bed was simulated. Experiment set different pulse parameter groups
Combined (shovel; t; heart), the simulation predicts the thickness of each part
Degree H (mm) corresponds to the cutting speed Vw, The test results are shown in the table
As shown in Figure 6 – 5, the corresponding test curve is given in Figure 6-17.
In Fig. 6-17, the curve
(1) i= 6A, t; = 6μs, t,. =30μs; curve
(2): ‘0i = 6 A, t; = 12μs, t., = 36 μs; Curve
(3) : t shovel = 12A, t; = 6μs, t. = 30μs; curve (4): i. = 12A,
t, = 48μs, t. = 144μs; curve (5): t, = 24A, t; = 24μs, t” = 120μs.