| The porous tricalcium phosphate ceramic( β-TCP),a kind of excellent material substituting bone. It can be biodegraded in biology body and effectively repair bone defects. However present preparation and shape technologies have difficulties in making porous bioceramics with controllable macrostructure. On the base of present preparation and shape technologies, in the paper a new preparation technology to make porous bioceramics with controllable macrostructure was invented.The method combined the hot pressure casting-shaping technique with organic foam small-sphere as pore-making reagent. Took β-TCP ceramics powder as base body, added in bioglass adhesive and organic foam small-sphere, and studied the different influence factors. Porous bioceramics was made and had the following characteristics: a high apparent porosity, β-dimension-through hole, high specific surface area and controllable macrostructure and hole rate and so on.The paper studied that β-TCP bioceramics powder was made and treated with by surface active agent, organic foam small-sphere was treated with, slurry was made, green body was shaped by hot pressure casting-shaping technique, and after prefired and sintered porous bioceramics were finally gained. And the controllability of macrostructure was studied. Capability of slurry, the changes of green body in sintering, and the capability of structure and the strength of porous bioceramics were tested and studied by different methods.The best technical parameters were gained as follows: the additive content of paraffin was 40%~60%; the mass ratio of organic foam small-sphere and β-TCP bioceramics powder was 0.2~0.5 when shaped by hand and the mass ratio was 0.1 ~ 0.25 when shaped by machine; the temperature of slurry was 60~80℃ and could use 5% or so oleic acid to improve slurry performance; compressive stress of shape was 0.3~0.5MPa, the time of steady stress was 1~5 seconds; in the phase of low temperature the speed of temperature rise was30~150℃/h, the constant temperature should be controlled low than 700℃; in the phase of higher temperature the speed of temperature rise was 100~300℃/h, the time of constant temperature was 2 hours or so.The results of physical capability indicated: the pores distributed orderly, the macro-pore and small pore and micro-pore connected one another; apparent porosity was high and volume weight was less than 0.7 g/cm3 ; the pervasion rate of water could be more than 2x10-2cm2 Pa; the compressive strength can be more than 1.6MPa.The results of analysis of controllability of macrostructure and hole rate indicated: macro-pore can be controlled by choosing the size and array order oforganic foam small-sphere; apparent porosity and connectedness of macro-pore can be controlled by the content of organic foam small-sphere.The results of the research testified that the technology was a kind of effective method, which could make a high apparent porosity, 3-dimension connectedness, high specific-surface porous bioceromics with controllable macrostructure, and make sample become solid only by cooling green body and easily take it from mould. Operation was simple, quick and economic, and the period of production was shorted too much; the complex production could easily be gained by designing mould or by processing beforehand. The technology was simple and economic, and could be extended in many fields, could not only easily be used in lab, but have industrializing application foreground.
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