Calcium stearate coated sand is to be applied

Lubricant coated sand is usually calcium stearate coated sand its fluidity,

caking resistance, gas evolution, has antimony trioxide  an impact strength and thermal

toughness. Calcium stearate coating evenly distributed in the sand, in the

core-temperature softening resin, and calcium stearate has melted, forming

a network interpenetrated softness of the resin increases, increasing the

deflection of the shell and thus lead to thermal toughness increases.

Calcium stearate-coated sand to improve lubricity fluidity that compaction

of the sand core is increased, thereby increasing the strength of the core.

Calcium stearate 60-80 degrees higher than the resin melting point, heat

softened after calcium stearate time later than the resin, dispersed in the

sand is not melted in a range of calcium stearate skeleton played a role in

the resin soften the sand barrier during settlement, reducing the formation

of voids and sand core expansion tendencies. But also can play a role in

improving the melting point of coated sand. Calcium stearate coated sand

can improve thermal cracking, thermal cracking of coated sand was mainly

due to thermal expansion and  red iron oxide thermal shock stress, with the increase in the

amount of calcium stearate, thermal cracking time gradually delayed, the

reason melting point higher than that of calcium stearate resin which

increases the sand core to improve the thermoplastic advantageous, whereby

relaxation of the thermal stress of the  tio2 anatase sand core. Calcium stearate was

added in the amount of coated sand although rarely, but the effect is very

large, to prevent caking of the coated sand, improve mobility, improve the

resistance of the shell and mold release. Calcium stearate coated sand not

only affect the quality of the strength of the coated sand temperature

performance is also crucial ten million can not be discounted. Calcium

stearate was added in the synthesis of a greater amount of silica can be

increased calcium stearate-coated sand in the high temperature performance.