The use of composite materials in aerospace and automotive applications has grown at a fast rate due to the high strength and low weight of the materials. Use of the material continues to grow despite its significantly higher raw material costs and relatively involved processing, frequently requiring expensive autoclaves or other pressure and heat-producing devices to compact and cure the materials. Another challenge of composites is their response to being drilled. This is especially true when the material is used in combination with a metal in a stack-up, e.g., composite and titanium. Drilling of the titanium layers creates much heat, which can thermally damage the resin matrix of the carbon fiber reinforced plastic (CFRP) layers. By using CO2 through-tool cooling, which is a dry process, it is possible to protect both layers. Researchers at Cool Clean Technologies have found through work supported by the U.S. National Science Foundation and U.S. Department of Energy. The work shows that CO2 through-tool can significantly increase productivity while maintaining required hole tolerances in both the composite and Ti layers. In addition, improvements in tool life have been demonstrated with CO2 through-tool cooling compared to either emulsion or dry drilling.
Learn more: http://articles.sae.org/13739/
Matumizi ya vifaa vya mchanganyiko katika matumizi ya anga na magari yamekua kwa kasi kwa sababu ya nguvu ya juu na uzito mdogo wa vifaa. Matumizi ya nyenzo hiyo yanaendelea kuongezeka licha ya gharama zake za juu zaidi za malighafi na usindikaji unaohusisha, mara nyingi unahitaji autoclaves ghali au vifaa vingine vya kushinikiza na joto ili kuunganisha na kuponya nyenzo. Tatizo jingine la vifaa vilivyofanyizwa kwa mchanganyiko ni jinsi vinavyokabiliana na kuchimbwa. Hii ni kweli hasa wakati nyenzo ni kutumika katika mchanganyiko na chuma katika stack-up, kwa mfano, composite na titanium. Kuchimba kwa tabaka za titani hutengeneza joto nyingi, ambalo linaweza kuharibu matrix ya resini ya tabaka za plastiki iliyoimarishwa na nyuzi za kaboni (CFRP). Kwa kutumia CO2 kupitia-chombo baridi, ambayo ni mchakato kavu, inawezekana kulinda tabaka zote mbili. Watafiti wa Cool Clean Technologies wamegundua kuwa, kwa sababu ya kazi ya utafiti, inaweza kuathiri afya ya binadamu. Kazi inaonyesha kwamba CO2 kupitia chombo inaweza kuongeza uzalishaji kwa kiasi kikubwa wakati kudumisha tolerances required shimo katika wote composite na Ti tabaka. Kwa kuongezea, maboresho katika maisha ya zana yameonyeshwa na CO2 kupitia-chombo baridi ikilinganishwa na ama emulsion au kuchimba kavu. Jifunze zaidi kuhusu: http: www.sw.org.uk