Precision Forming Technology Research On Rubber Bladder Forming Of Aircraft Titanium Alloy Sheet Metal

Sheet metal forming technology is one of the most important supportive technologies in theaircraft manufacturing engineering. With the development of science and technology, aircraft sheetmetal forming technology is developing in the direction of non-fixed allowance, and it is so strict tothe quality of sheet metal forming that no multiple cold work hardening or scratches is allowed.What’s more, it is need to realize the digital quantity transfer and numerical control processingequipment have made the sheet metal forming technology enter into the stage of precise forming.Rubber fluid forming is one of the commonly used methods of precise forming of sheet metal.For China’s large aircraft manufacturing and production requirements, its components are complex,precision production, more varieties, high quality and short delivery time. As a traditionalmanufacturing technology, rubber bladder forming has played an important role in aviationmanufacturing industry. But how to make the rubber bladder forming technique combined with finiteelement analysis technology to meet the need of the rapid development of aviation manufacturingindustry is the focus of this paper.In this paper, rubber bladder precise forming with CP3titanium alloy sheet metal parts has beenstudied. First, measure the basic mechanics performance parameters of titanium CP3such as elasticmodulus, yield strength, tensile strength, hardening exponent, and the true stress strain curve throughexperiments. Mechanical properties of materials are an important factor affecting the accuracy offinite element simulation. Test the forming limit curve of titanium CP3to analysis the local forminglimit of sheet mental quantitatively and qualitatively. Study influence factors on rubber bladderforming simulation accuracy such as sheet unit model, the number and the density of units, numbersof the integral point to thickness. Then study the rubber bladder forming finite element simulation andspring back compensation of a typical straight flanging part with PAM-STAMP2G2011macrotechnology. Validate the simulation results with experimental results of parts to achieve the planetitanium alloy sheet metal rubber bladder forming precision requirements, finally to guide the actualprocess of aircraft manufacturing.