Production status of copper alloy profiled copper tapes for lead frames: Copper tapes for lead frames are currently not mass-produced in China. Even small-scale trial-manufactured products have one or more problems. Compared with the requirements of users and foreign counterparts, Differs greatly. Mainly manifested in
Good strength: Whether the lead frame is in the packaging process, or in the subsequent test and the customer is inserted into the printed circuit board during use, they are required to have good tensile strength. The tensile strength of Fe58% -Ni42% iron-nickel alloy is 0.64GPa, while the tensile strength of copper material alloy is generally below 0.5GPa, so the tensile strength of copper material is slightly worse, it can also be doped Improve tensile strength. As a lead frame, it is generally required that the tensile strength should be at least 441MPa, and the elongation is greater than 5%.
Continuous extrusion-stretching method is a new technology developed in China in recent years. It utilizes the advantages of continuous extrusion, adopts continuous casting rod material to continuously extrude into special-shaped strip blanks, and is rolled out and taken out after cleaning and mold stretching.
Advantages: Compared with the forging-rolling method, the process is simple and the process is short. The flat belt used in the forging-rolling method needs to go through more than 20 processes from melt casting to flat strip billet. The forging-rolling method itself also needs to undergo uncoiling, welding, forging preforming, trimming, annealing, cleaning, shaping rolling, coil It takes 8 steps; while the continuous extrusion-stretching method only takes 8 steps from the beginning of melting casting to the winding of the finished product. Secondly, the continuous extrusion-stretching method has high production efficiency, and the annual production capacity of an upward-continuous-extrusion-continuous-drawing production line can reach 4000-5000 tons.