| 摘要 |
<p>A mould or core is made, esp. for casting molten metal, where a pattern is coated with a slurry consisting of two liqs., >=1 liq. contg. refractory powder(s). The two liqs. are stable, but when sprayed on the pattern they combine to form a rigid coherent gel. Each liq. is pref. held in a reservoir and fed to a separate nozzle. One liq. pref. contains a binder and a retarder hindering gel formation, whereas the other liq. contains an accelerator promoting gel formation. The binder is pref a Zr salt producing an acid or alkaline aq. soln. and contg. a retarder, viz. magnesium-acetate or lactate, ammonium lactate, glycine, betaine, fructose, or polyvalent alcohols, where the accelerator is an amino-alcohol, morpholine, calcined MgO powder, possibly in spinels. Used for the casting of ferrous or nonferrous metals.</p> |
