Aluminium Radiator profiles from the ingot of the quality, mold material and design, reduce the extrusion pressure and extrusion process and so on.
1, the quality requirements of ingots
Ingredients of the ingot to strictly control the impurity content, to ensure that the alloy is extremely clean. For 6063 alloy to control the Fe, Mg, Si content. Fe content should be less than 0.2%, Mg, Si content are generally controlled in the lower limit of national standards,Aluminium Radiator Mg content of 0.45% ~ 0.55%, Si content of 0.25% to 0.35%. Ingredients to go through the full homogenization of the ingot of the organization, the performance of uniform.
The surface of the ingot is smooth and does not allow segregation or sticky sand. The end face of the ingot should be flat and can not be cut into steps or cut too much (cut slope should be within 3 mm). Because the stepped or cut slope is too large, with the plane die extrusion heat section, if there is no design diversion, the ingot directly hit the mold, due to ingot face uneven, there are places before touching the mold, resulting in stress concentration , Easy to die out of the mold, or cause the material is different, easy to produce plugging or extrusion molding is not good phenomenon.
2, the requirements of the mold
Because the radiator profile mold is a lot of slender teeth, to withstand a lot of squeeze, each tooth must have a high strength and toughness, if the performance between each other is very different, it is easy So that those teeth with poor strength or toughness are broken. Therefore,Aluminium Radiator the quality of mold steel must be reliable, it is best to use the quality of reliable manufacturers of H13 steel, or the use of high-quality imported steel. Mold heat treatment is very important, use vacuum heating quenching, the best use of high pressure nitrogen quenching, can ensure that the mold after the various parts of the uniform performance. After quenching to take three tempering, so that the hardness of the mold to ensure that under the premise of HRC48 ~ 52, with sufficient toughness. This is an important condition to prevent the mold from breaking teeth.
Radiator profiles to be able to successfully squeeze success, the key is to design a reasonable mold, manufacturing to be accurate. Generally try to avoid the direct extrusion of the ingot to the mold work belt. For the flat width of the comb-shaped radiator profiles, the design of a smaller middle,Aluminium Radiator both sides of the larger diversion die, so that the metal flow to both sides to reduce the extrusion work on the mold pressure, and make the pressure distribution evenly. As the radiator profile cross-section of the wall thickness difference, the design of the mold work belt to maintain their corresponding differences, that is, wall thickness of the local work belt to be particularly increased, can be as large as 20mm ~ 30mm, and the location of the tooth to break Routine, the work belt to a minimum. In short, to ensure that the flow of metal throughout the uniformity. For flat wide-shaped radiator, in order to ensure that the mold has a certain stiffness, the thickness of the mold should be increased. Thickness increase of about 30% to 60%. Mold production must also be very fine, empty knife to do up and down, left and right, the middle to maintain symmetry, teeth and teeth between the processing error is less than 0.05mm, the processing error prone to partial teeth, the thickness of the heat sink is not uniform, Even the phenomenon of broken teeth.
For the design of more mature cross-section, with the embedded alloy steel mold is also a better way, because the alloy steel mold has good rigidity and wear resistance, easy to produce deformation,Aluminium Radiator is conducive to the radiator profile forming.
3, reduce the squeeze force
In order to prevent the mold broken teeth should minimize the extrusion force, and the extrusion force and the ingot long, alloy deformation resistance of the size of the ingot state, the degree of deformation and other factors. Therefore, the extrusion of aluminum casting rods should not be too long, about the normal length of the cast rod (0.6 ~ 0.85 times). Especially in the test mode and squeeze the first cast rod,Aluminium Radiator in order to ensure the successful production of qualified products, it is best to use a shorter cast rod, that is, the length of the normal cast rod (0.4 to 0.6) times the cast rod to try mold.
For the shape of the complex heat shouting profiles section, in addition to shorten the length of cast rods, but also consider the use of pure aluminum short cast to do the first test extrusion, test squeeze successful and then use the normal ingot extrusion production.
Ingredient homogenization annealing not only makes the organization and performance uniform, but also can improve the extrusion performance and reduce the extrusion force, so the ingot must be homogenized annealing. As for the impact of the degree of deformation, because the radiator profile of the cross-sectional area are generally larger, the extrusion coefficient is generally less than 40, so its impact is small.
4, extrusion process
Radiator profile production is the key to squeeze the mold of the first test mode, conditional, you can first do a simulation test on the computer to see the work of the mold design is reasonable, and then try on the extruder. The first test mode is very important, the operator to make the main plunger forward pressure in the low pressure below 8MPa under the slow forward, it is best to use a flashlight to take care of the mold exit,Aluminium Radiator and so on each of the extrusion die cooling The film is evenly squeezed die hole, in order to gradually pressure to accelerate the extrusion. Try to continue after the success of extrusion, should pay attention to control the extrusion speed, so smooth operation. Production of radiator profiles should pay attention to the heating temperature of the mold, mold temperature and the ingot temperature to close. If the temperature difference is too large, because the pressure on the extrusion speed is slow, will make the metal temperature drop, easy to produce blocking or flow rate uneven phenomenon.