LOM technology squeezes the research of the ceramics that make a surname mediumly

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Statified and hypostatic modelling (Laminated Object Manufacturing, abbreviation LOM) is will filmy material the Laser Cutting that chase a layer wants form into place, fold the shaping method that add in next. LOM is new technology of a kind of fast figuration. It will be traditional " purify " treatment method change is " increase " treatment method. LOM technology is integrated CAD, laser, actinic wait for a variety of technologies with high polymer polymer. Its fundamental is, above all according to products plan blueprint or " beg instead " the law gets a series of cross section, the contour line that stimulates beam of light to press each with numerical control undertakes machining to paper or other sheet and overlay, till finish whole make. LOM technology need not machining or any moulds, make from what CAD model makes complex appearance directly, consequently the product develops cycle to shorten, productivity rises, manufacturing cost is reduced [1 ~ 3] . Pottery and porcelain of project of preparation of applied LOM technology, want green compact of preparation contented ceramics above all, machine figuration to be complex pottery and porcelain next green compact, again defatted agglomeration, end up with complex pottery and porcelain. The research that the United States has to LOM technology is more [4 ~ 6] . Current, the method of the contented ceramics that preparation LOM technology uses basically is to flow delay law and push a way [7] . This experiment introduces the Al2O3 of crowded preparation giving a way and green compact of SiC contented ceramics, ply is 0.

2mm, organic matter carrier is low density polyethylene. 1 experiment 1.

Preparation of 1 contented ceramics presses powder of 2 μ MAl2O3 and LDPE grain weight to compare 80 ∶ 20 mix together. Load mixture extruder of Haake-RC90 system double screw, build bead, squeeze piece. Same method makes blank of ceramics of equipment SiC contented. Graph 1 for curve of pulverous particle size distribution, graph 2 for pulverous form appearance. Graph Fig of 1 pulverous particle size distribution.

1Grain Size Distribution Of Powders pursues the SEM photograph of 2 powder (A)Al2O3; (B)SiCFig.

2SEM Micrographs Of Ceramic Powders (a)Al2O3; (B)SiC Nextpage1.

2 shed denaturation to be able to study what compare content of bulk of pink of different pottery and porcelain on Haake-RC90 system to shed denaturation can. Discuss condition of identical bulk content to fall, pulverous granuality and temperature convection change the influence of function. 1.

In air of 3 child analysis, undertake to contented ceramics green compact TG-DTA heats up an analysis. Undertook to child microcosmic organization analyses SEM. 2 results and discuss 2.

1 shed denaturation to be able to analyse a scheme 3 cut stress and cut curve of meet an emergency (A) and apparent viscosity and cut curve of meet an emergency (B)Fig.

3Shear Stress (a) And Apparent Viscosity (b) As Function Of Shear Rate With Alumina Content(1)LDPE; (2)60wt%Al2O3; (3)70wt%Al2O3; (4)80wt%Al2O3; (Of the mixture of content of 5)85wt%Al2O3   different Al2O3 stream change the curve is likeness, present feature of body of plasticity giving a holiday. Graph 3a falls for 463K condition, the cutting of the mixture of different Al2O3 content stress and cut curve of meet an emergency. Cut stress τ to increase and increase along with what cut ′ of γ of meet an emergency, both logarithm concerns for linear, satisfy relation: ′ of γ of App of η of N= of ′ of τ =c γ (the C in 1) type and N are constant. App of apparent viscosity η can express to be: η App= τ / the apparent viscosity of the mixture of content of different Al2O3 of   of N-1 (2) of ′ of γ of γ ′ =c and if graph 3b place is shown,cut curve of meet an emergency. Experimental result presses type (1) returns to processing, the result shows N follows Al2O3 to content increases and be reduced, c increases along with Al2O3 content and increase. In craft of contented ceramics figuration, content of pottery and porcelain should as far as possible big, however, increase as content of pottery and porcelain, cut stress to increase, cannot squeeze even piece. Pulverous to 2 μ MAl2O3, it is appropriate that content is 75wt%(42vol%) , right now, contented ceramics can be squeezed smoothly go out and can become roll. And pulverous to 5 μ MSiC, content is 75wt%(47vol%) had better. Graph 4a shows a temperature the influence to cutting stress, the result makes clear, elevatory meeting drops temperature cut stress, and this change is successive, did not change suddenly. Graph 4 cut stress and temperature (A) and pulverous granuality (the granuality of relation 75wt%Al2O3 powder of B) (A)2 μ M;(b-1)2 μ M; (B-2)10 μ M; (B-3)40 μ MFig.

4M of μ of Shear Stress As Function Of Temperature(a) And Particle Size (b) With 75wt% Al2O3 Content And Particle Size(a)2; (B-1)2 μ M; (B-2)10 μ M; (4b of graph of   of B-3)40 μ M shows a condition of content of identical pottery and porcelain to fall, the pulverous size influence to cutting stress. The result shows: Pulverous size is large, make cut stress to reduce, this and pulverous attrition area are concerned; Powder is fine, express an area to increase, attrition aggravate, expression increases to cut stress, the theoretical calculation when this and solid content are little differs as a result. Nextpage2.

2 hot analysises and microcosmic organization analysis are in air, undertook TG-DTA is analysed, see a picture 5. The result makes clear, there are 3 big radiative peaks to appear in 245 ~ in the DTA curve of Al2O3-LDPE sample 375 ℃ , weightlessness of temperature interval sample is very here fast. There are 3 big radiative peaks to appear in 421 ~ in the DTA curve of SiC-LDPE sample 500 ℃ , temperature interval is smaller, weightlessness is faster. In 95 ℃ , both DTA curve has peak of one small absorption of heat, this is the melting point of LDPE. To Al2O3-LDPE, 375 ℃ of 245 ~ are crucial temperature interval, to SiC-LDPE, 500 ℃ of 421 ~ are crucial temperature interval. In this temperature interval, LDPE oxidation is decomposed very acuteness, what this decided defatted craft is medium is the biggest increase hot rate. Graph base of 5 pottery and porcelain piece TG-DAT is analysed (A)Al2O3; (B)SiCFig.

5Simultaneous TG-DAT Analysis On Green Tape, ℃ of Up To 600 (A)Al2O3; (B)SiC   uses SEM to undertake microcosmic organization is analysed, see a picture 6. Look from the result, it is even that particle of pottery and porcelain distributings mediumly in LDPE matrix, and maintained their original form appearance, particle of pottery and porcelain and LDPE do not produce reaction. Graph 6 contented ceramics is microcosmic organization (A)Al2O3; (B)SiCFig.

6Microstructural Features Of Surface Of Tapes (a)Al2O3; (B)SiC3 conclusion uses crowded preparation giving a way the Al2O3 that is used at LOM technology and blank of SiC contented ceramics, ply is 0.

2mm. To 2 μ MAl2O3 pink, content of pottery and porcelain is 75wt%(42vol%) , interval of defatted and crucial temperature is 245 ~ 375 ℃ . Pulverous to 5 μ MSiC, content of pottery and porcelain is 75wt%(47vol%) , interval of defatted and crucial temperature is 421 ~ 500 ℃ . CNC Milling