The material of the hydroforming classification and requirements is divided into low carbon steel, stainless steel and aluminum alloy. The requirements of the pipe include mechanical properties, forming properties, wall thickness precision, cleanliness, etc.

the metal tube hydroforming function:

1) Low carbon steel, two-way steel 1. Tensile strength: 290-440MPa; 2. Trend: The tensile strength reaches 590-780 MPa, even reaching 980 MPa. 2) Stainless steel: austenitic stainless steel 304, 1cr18Ni9T; ferritic stainless steel 429, 309 Used in engine manifolds (heat and oxidation resistant). 3) Aluminum alloy: 5000 series, 6000 series and 7000 series 1. Aircraft and rocket pipe fittings: 5000 series aluminum alloy pipe; 2. Automobiles and bicycles: 6000 series aluminum alloy pipes; 3. Titanium alloy: pure titanium and Tc4. 4) Cleanliness: The inner and outer surfaces of the hydroformed tube should be clean. The surface of the steel pipe should be pickled and free of scale. During hydroforming, surface rust and scale can cause excessive tool wear and contaminate the hydroforming fluid. Any chips inside or outside the tube may be flushed into the tool cavity and embedded in the surface of the hydroformed part. 5) Dimensional tolerances: For tubes made of hot rolled and cold rolled steel to ASTM A513 specifications (Steel Tube Society 1994), the outer and thickness tolerances are between Tables 9-3 and 9-6. Most supply tubes are very close to the nominal size of the tube OD and thickness and have sufficient hydroforming process. Based on the fluid sealing method, process parameters and TTEOTOL may require some changes to different batches of material. The required tube length tolerance is ±0.60 inches (1.5 mm). For some end seal methods, this tolerance may be significantly higher. 6) End conditions: The tube end must be cut into a square with the centerline of the tube, approximately within 1.5. Acceptable degrees of loss and degree of end deformation also depend on the end seal method, which also dictates that the ends need to be chamfered outside or inside the tube diameter.