Precision casting, also called investment casting
Casting precision, surface smoothness, texture density and metallographic structure produced by sand casting are usually varied, so requirements for these properties in casting are higher, other casting methods such as investment casting, pressure casting, low pressure casting and so on should be adopted. Introduction is specified below:
I. Characteristics and advantages of precision casting
Precision casting, also called investment casting, has the following characteristics when compared with other casting methods and component shaping methods:
1. Dimensional precision of casting is high and surface roughness height is low; dimensional precision of casting can reach grades 4-6, and surface roughness can reach 0.4-3.2μm, which can drastically bring down working allowance of casting, realize no-allowance manufacturing and decrease production cost.
2. Casting shapes are complicated and other methods prove difficult to be used for processing castings; overall dimension of castings ranges from several millimeters to thousands of millimeters; wall thickness is 0.5mm at the thinnest and the minimum hole radius is below 1.0mm.
3. Alloy materials are not limited. For example, such materials as carbon steel, stainless steel, alloy steel, copper alloy, aluminum alloy, high-temperature alloy, titanium alloy and precious metals can all be used for precision casting production. Alloy materials that cannot be easily forged, welded or cut are particularly suitable for precision casting.
4. It has high production flexibility and is well-adapted. It can be used for mass production, small-scaled production and single-piece production.
To sum up, precision casting has the advantages such as small investment scale, high production capacity, low production cost, simplified production technique and fast yielding for investment. It thus seizes the advantageous position in its competition with other techniques and production means and enjoys promising prospects.