Surface-treatment method for rapid-manufactured three-dimensional objects

1. A method for forming a surface-treated, three-dimensional object, the method comprising:

placing a rapid-manufactured, three-dimensional object in a vapor smoothing chamber, the rapid-manufactured, three-dimensional object compositionally comprising a thermoplastic material, and having an exterior surface that includes surface effects due to a layer-by-layer, rapid manufacturing technique;

vapor smoothing the exterior surface of the rapid-manufactured, three-dimensional object with a solvent vapor in the vapor smoothing chamber to reduce or eliminate the surface effects;

monitoring a specular diffusivity of the exterior surface;

discontinuing the vapor smoothing step when the specular diffusivity of the exterior surface reaches a first predetermined level, wherein the resulting smoothed three-dimensional object has a solvent-smoothed exterior surface with a higher glossiness than the exterior surface prior to the vapor smoothing step;

media blasting at least a portion of the solvent-smoothed exterior surface to provide a burnished exterior surface;

monitoring a specular diffusivity of the solvent-smoothed exterior surface; and

discontinuing the media blasting when the specular diffusivity of the solvent-smoothed exterior surface reaches a second predetermined level, wherein the burnished exterior surface has a lower glossiness than the solvent-smoothed exterior surface prior to the media blasting step.

2. The method of claim 1 , wherein the vapor smoothing step reduces a porosity of the three-dimensional object at the exterior surface.

3. The method of claim 1 , wherein the solvent vapor uses a solvent selected from the group consisting of methylene chloride, n-propyl bromide, perchloroethylene, trichloroethylene, acetone, methyl ethyl ketone, dimethylacetamide, xylene, toluene, water, alcohols, and combinations thereof.

4. The method of claim 1 , further comprising cooling the rapid-manufactured, three-dimensional object below room temperature prior to smoothing the exterior surface.

5. The method of claim 1 , wherein placing the rapid-manufactured, three-dimensional objet in the vapor smoothing chamber comprises suspending the rapid-manufactured, three-dimensional object from a hook-like member in the vapor smoothing chamber.

6. The method of claim 1 , further comprising abrasively removing at least one surface blemish from the solvent-smoothed exterior surface.

7. The method of claim 1 , wherein the media blasting comprises blasting with sodium bicarbonate.

8. A method for forming a surface-treated, three-dimensional object, the method comprising:

building at least a portion of a three-dimensional object from a thermoplastic material with a layer-by-layer, rapid manufacturing technique, the three-dimensional object having an exterior surface that includes surface effects due to the layer-by-layer, rapid manufacturing technique;

placing the built three-dimensional object in a vapor smoothing chamber;

vapor smoothing the exterior surface with a solvent-based vapor smoothing process in the vapor smoothing chamber to reduce or eliminate the surface effects;

monitoring a specular diffusivity of the exterior surface;

discontinuing the vapor smoothing process when the specular diffusivity of the exterior surface reaches a first predetermined level, wherein the resulting smoothed three-dimensional object has a solvent-smoothed exterior surface with a higher glossiness than the exterior surface prior to the vapor smoothing step;

placing the smoothed three-dimensional object in a media blasting system;

media blasting at least a portion of the solvent-smoothed exterior surface while the smoothed three-dimensional object is disposed in the media blasting system;

monitoring a specular diffusivity of the solvent-smoothed exterior surface; and

discontinuing the media blasting when the specular diffusivity of the smoothed exterior surface reaches a second predetermined level, wherein the burnished exterior surface has a lower glossiness than the solvent-smoothed exterior surface prior to the media blasting step.

9. The method of claim 8 , wherein the vapor smoothing step reduces a porosity of the three-dimensional object at the exterior surface.

10. The method of claim 8 , further comprising cooling the built three-dimensional object below room temperature prior to vapor smoothing the exterior surface.

11. The method of claim 8 , wherein the media blasting comprises blasting with sodium bicarbonate.

12. A method for forming a surface-treated, three-dimensional object, the method comprising:

providing a three-dimensional object at least partially built with a layer-by-layer, rapid manufacturing technique using a thermoplastic material, the three-dimensional object having an exterior surface that includes surface effects due to the layer-by-layer, rapid manufacturing technique;

placing the three-dimensional object in a vapor smoothing chamber;

reducing or eliminating the surface effects of the exterior surface with a solvent-based, vapor smoothing process in the vapor smoothing chamber to provide a solvent-smoothed exterior surface having a higher glossiness than the exterior surface prior to the solvent-based, vapor smoothing process;

monitoring a specular diffusivity of the exterior surface during the solvent-based, vapor smoothing process;

discontinuing the vapor smoothing process when the specular diffusivity of the exterior surface reaches a first predetermined level, wherein the resulting smoothed three-dimensional object has a solvent-smoothed exterior surface with a higher glossiness than the exterior surface prior to the vapor smoothing step;

media blasting at least a portion of the solvent-smoothed exterior surface;

monitoring a specular diffusivity of the solvent-smoothed exterior surface during the media blasting step; and

discontinuing the media blasting when the specular diffusivity of the solvent-smoothed exterior surface reaches a second predetermined level, wherein the burnished exterior surface has a lower glossiness than the solvent-smoothed exterior surface prior to the media blasting step.

13. The method of claim 12 , wherein the solvent-based vapor smoothing process uses a solvent selected from the group consisting of methylene chloride, n-propyl bromide, perchloroethylene, trichloroethylene, acetone, methyl ethyl ketone, dimethylacetamide, xylene, toluene, water, alcohols, and combinations thereof.

14. The method of claim 12 , further comprising cooling the rapid-manufactured, three-dimensional object below room temperature prior to the vapor smoothing process.

15. The method of claim 12 , wherein the media blasting comprises blasting with sodium bicarbonate.

16. The method of claim 12 , wherein providing the three-dimensional object that is at least partially built with the rapid manufacturing technique comprises building the three-dimensional object in a layer-by-layer manner using the rapid manufacturing technique.

17. The method of claim 12 , wherein the surface effects of the exterior surface comprise stair-step effects.