Phosphor bronze strip with good elasticity is generally used in plug-in materials, widely used in automobile, electronic communication mobile phone and other industries; Domestic market demand for 180,000 tons, of which 70,000 tons to the composition of nickel content in about 0.3 phosphorus.
1. Phosphor bronze is all produced by horizontal continuous casting process, and most of the raw materials are produced by Angle material and new material; Due to the impact of copper prices, the old and new materials have been the difference. The nickel content of all high-precision phosphor bronze should be controlled within the range of 0.08%-0.10%. The nickel content of processing and outsourcing corner materials should be strictly controlled, and personnel should be organized to pick the diagonal materials. Generally, high magnetic absorption is used to mix iron slag in Angle material.
2. Formula ratio: Formula ratio is generally adjusted according to the price difference between old and new materials, C5191 and C5210 are generally within the range of 10-20% and 20-30%. In order to reduce the amount of tin added per furnace, it is generally recommended to cut tin ingots into small pieces; Different raw materials are proportioned by the raw material preparation section and loaded into the iron bucket; Added to melting furnace by horizontal continuous casting operator.
3. Horizontal continuous casting management: Measure the casting temperature of each furnace according to the process. If the proportion of Angle material is large, it is generally recommended to use molten shuo for each furnace. With a wooden rod fully stir, with waste graphite made of scooping shovel for artificial slag removal. Add the drying charcoal, add the milling dust foam for drying packaging, reduce the loss and oil. When pouring into the insulation furnace at the end of casting, the flow nest must be cleaned to prevent cold copper from rushing into the mold. The temperature difference of each furnace is controlled at about 10 degrees, and the temperature of the insulation furnace should be measured regularly. Always clean the copper around the insulation furnace.
4. According to the mold loading: the mold is generally Vitelli structure, replaced by the mold should be cleaned, copper sleeve regular smooth grinding; According to the mold loading quality depends on the worker skills, general graphite can be repaired; Basically using imported graphite. Dry according to loading.
6. Horizontal continuous casting mold exchange: the core of horizontal continuous casting is horizontal, and infrared radiation is used before the mold exchange. It is suggested that the horizontal continuous casting insulation furnace should be fixed by sitting low to prevent the deviation of crack edge or even copper leakage in the drawing process. Clean the window, must be smooth, crystallizer according to the installation of good control of water temperature; There are several production enterprises with temperature equipment; When the mold is installed, the flow rate is controlled to improve the water temperature when the heat preservation furnace is put in. Make the point of the blank crystallization line less than 6mm, the outlet temperature is higher than 300 degrees (super nickel material is also higher); At present, electromagnetic casting can improve the reverse segregation of refined grains. From the mold management to the replacement of the focus of attention in anti-segregation, because the equipment personnel process is different each has a trick; I'm not going to describe it.
6. Process control: In order to refine grains and reduce reverse segregation, it is suggested to roll the billet into core-free coiling one time in roughing mill, cancel the homogenization annealing and switch to recrystallization annealing. After annealing, milling surface is recommended to be 0.6mm up and 0.7mm down; Into the rough rolling generally eight times rolling to 1.0-1.2 range; At this time, the junction particle size is about 0.15mm. Rough rolling control plate shape, prevent adhesion caused by tin overflow phenomenon; When entering the thick wash, a grinding brush is added in front to eradicate the adverse defects caused by the front passage, such as skin scrapes; This channel is the quality control point, and hierarchical management based on the product surface is conducive to production scheduling. Typical defects are reverse segregation, broken crystal, black spots and so on.
In summary, the principle of low temperature and fast speed is followed in the crystallinity control, especially the temperature control of the air cushion furnace is the focus of the production of crystalline phosphorus copper. Since the quality of the front channel of phosphor bronze production accounts for 70%, the basic lean production of the back channel will not be described.
