通过对脱脂动力学的分析,发现在脱脂过程中,存在动力学控制步骤转化的过程,提出了临界厚度的概念.临界厚度越大,意味着脱脂初始阶段升温速率可以较快,脱脂所需时间可以相对缩短.临界厚度越小,那么脱脂初始阶段必须缓慢升温,以免产生鼓泡、裂纹、变形等缺陷.生产实践中临界厚度越大,脱脂处理越容易进行.对脱脂过程中控制步骤的理论计算,得到脱脂临界厚度与粉末大小、脱脂温度和装载量的关系:临界厚度与粉末颗粒大小成正比,粉末颗粒越大,临界厚度也大;临界厚度与保温温度成反比关系,温度越高,临界厚度越小;临界厚度与装载量成反比,装载量越高,临界厚度越小.
参考文献
| [1] | 高建祥,曲选辉,赵赛,范景莲,祝宝军.硬质合金注射成形多组元聚合物粘结剂的溶剂脱脂工艺研究[J].稀有金属材料与工程,2003(11):934-938. |
| [2] | 李益民,曲选辉,李志林,黄伯云.粉末装载量对W-Ni-FemIM合金喂料粘度及力学性能的影响[J].稀有金属,1999(01):21-24. |
| [3] | Wiech R E .[P].US Patent 4305756,1981. |
| [4] | Cima M J;Lewis J A;Devoe A D .Binder Distribution in Ceramic Greenware During Thermolysis[J].Journal of the American Ceramic Society,1989,72(07):1192. |
| [5] | Shaw H M;Edirisinghe M J .Removal of Binder from Ceramic Bodies Fabricated Using Plastic Forming Methods[J].American Ceramic Society Bulletin,1993,72(09):94-99. |
| [6] | Dong C;Bowen H K .Hot-Stage of Bubble Formation During Binder Burnout[J].Journal of the American Ceramic Society,1989,72(06):1082. |
| [7] | Calvert P;Cima M .Theoretical Models for Binder Burnout[J].Journal of the American Ceramic Society,1990,73(03):575. |
| [8] | Barone M R;Ulicny J C .Liquid-Phase Transport During Removal of Organic Binder in Injection-Molded Ceramics[J].Journal of the American Ceramic Society,1990,73(11):3323. |
| [9] | Angermann H H;Biest O O V D .Low Temperature Debinding Kinetics of Two-Component Model Systems[J].International Journal of Powder Metallurgy,1993,29(03):239-250. |
| [10] | Matar S A;Edirisinghe M J;Evans J R G et al.Diffusion of Degradation Products in Ceramic Moldings During Pyrolysis:Effect of Geometry[J].International Journal of Powder Metallurgy,1987,23(04):237. |
| [11] | German R M .Theory of Thermal Debinding[J].International Journal of Powder Metallurgy,1987,24(03):237. |
| [12] | Masia S;Calvert P D;Rhine W E et al.Effect of Oxides on Binder Burnout During Ceramics Processing[J].Journal of Materials Science,1989,24:1907. |
| [13] | Nogueira F Q;Edirisinghe M J;Gawne D T .Selection of A Powder for Ceramic Inection Moulding[J].Journal of Materials Science,1992,27:6525. |
| [14] | Wright J K;Evans J R G;Edirisinghe M J .Degradation of Polyolefin Blends Used for Ceramic Injection Molding[J].Journal of the American Ceramic Society,1989,72(10):1822. |
| [15] | Edirisinghe M J .Binder Removal from Moulded Ceramic Bodies in Different Atmosphere[J].Journal of Materials Science Letters,1991,10:1338. |
| [16] | Lewis JA.;Bentz DP.;Galler MA. .COMPUTER SIMULATIONS OF BINDER REMOVAL FROM 2-D AND 3-D MODEL PARTICULATE BODIES[J].Journal of the American Ceramic Society,1996(5):1377-1388. |
| [17] | Duda J L;Vrentas J S et al.Prediction of Diffusion Coeffi- cients for Polymer-Solvent Systems[J].AICHE Journal,1982,28(02):279. |
| [18] | 李益民 .金属注射成形石腊基粘结剂和油基粘结剂性质的研究[D].中南工业大学,1998. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%