Design guide for AlSiC Products
Though AlSiC composite material has many advantages, advantage might be disadvantage some time. For example, AlSiC is wear resistant material, good to make brake pad for racing car and plane, it is then hard to machine. Therefore, net-shaped casting logically becomes one character of AlSiC product process. Unlike traditional casting process, which could not cast melted Al into ceramic, AlSiC casting environment is somehow much more hi-end. Common mold materials adopted by precision casting do not fit the environment. Take example of ceramic mold shell, the most commonly used material in precision casting, do not fit in AlSiC processing, the melted Al will be cast into the mold and the AlSiC product will not be knocked out.
Then what is the feature of AlSiC infiltration casting, how to design the AlSiC product to lower its cost while keep the function of AlSiC product? Some AlSiC product design principles are listed below for designer's reference ( of couse, you do not have to worry about all this, just send us your drawing, how you want to use the material and the using environment, we will design the product requested and send back to you for audit ):
1. dimension precision: AlSiC material is isotropic, which ever the direction, the dimension precision should not be tighter than 1.5/1000.
2. flatness: AlSiC net-shaped casting could reach 0.75/1000
3. surface roughness: 1.6 micrometers for simple shaped products, 3.2 micrometers for complex shaped products. By special requirement, polishing process is available.
4. design as less threaded hole and round hole as possible, whenever U shaped holes do the same job, better use U shaped holes. For more detail, please refer to the design principle of U shaped holes.
5. draft angle is not always necessary. But when the thickness exceeds 10mm, or U shaped holes and sometime pin fin design applies, at least 5°draft angle is needed.
6. better design AlSiC product the way it fit for split mold to produce, and better put the biggest flat surface on one top side to eliminate the parting line. For detailed information, please press here.