Used for precision casting moulding material shall meet the requirements

Manufacturing investment pattern material called die material. In order to get high quality investment pattern, must choose the right mold material. Due to the precision casting process is more, so to die material performance requirements is also various. Used for precision casting the moulding material should be in the following performance meet certain requirements.
1. The weldability. Die material weldability said die material mutual joint performance. Will individual investment pattern combination ChengMo group, request die material has good welding performance and high welding strength, so it is easy to melt die combination, and avoid module in transportation and system shell since breaking when soldering.
2. Smearing property. Die material for refractory coating of wetting affinity performance called smearing property. System shell, for investment pattern surface can be fireproof paint good wetting, evenly coated with a layer of. Die material smearing property has a direct influence on the inner cavity of the mold shell shape complete and the surface is bright and clean.
3. Melting point. Suitable for precision casting production of die material used its melting point shoulds not be too high or too low, generally in the ℃ ~ 100 ℃ range. Because according to the die materials of general performance, melting point moderate, melting mould has certain strength and thermal stability; At the same time easy to match mold material, preparation and melting loss of investment pattern, the adaptation production mechanization and automation and shorten the production cycle requirements.
4. Shrinkage. Die material shrinkage with "round cakes sample" in a certain temperature range when the percentage change in the diameter of the cooling said. To die material shrinkage requirements, general hope less than i. 2%, make investment pattern not appear shrink defects such as concave, and its value stability. Die material shrinkage of small, can make the investment pattern size closer to the size of the mold cavity, and can reduce the cooling of distortion, so as to ensure the accuracy of investment pattern.
5. Thermal stability. Standard test cheung in heating, the deformation deflection of 2 mm when the temperature of mold material softening point that thermal stability. Die material softening point should not be commonly below 35 ℃ ~ and ℃, otherwise in the summer it was difficult to ensure that the investment pattern of strength and precision. According to the practical experience, die material softening point should be better than moulding and system shell work site temperature above 10 ℃ ~ 15 ℃ advisable.
6. Liquidity. Die material in certain conditions filling mold cavity ability called liquidity. Die material should have good liquidity, like this is advantageous to the full and clear duplicate mold cavity surface, thus obtains the shape accuracy and the surface is bright and clean the investment pattern; At the same time, also facilitate die material melt out from the mold shell.
7. Strength and plasticity. Die material strength normally with standard sample bending and tensile strength said. In order to ensure investment casting in combination, storage and system in the process of shell, etc, the move, vibration, impact under the action of no damage, deformation or less deformation, which requires the die materials at room temperature have enough mechanical properties. Used for small die material its tensile strength best more than 1.4 MPa, and big die material shall be not less than 2.5 MPa.