对灰铸铁中D型石墨的评价

对灰铸铁中 D 型石墨的认识一直存在分歧、影啊正确评价 D 型石墨的原因是多方面的,奥氏体技晶常与 D 型石墨同时出现是其中的原因之一。由于 CE 相同时,枝晶数量多少对灰铸铁强度有明显影响.因而以前那些没有考虑枝晶的影响所作出的对 D 型石墨的评价是欠说服力的。文中通过控制枝晶数量,基体组织和石墨类型,对不同 CE 下 A 型石墨、D 型石墨及枝晶对强度的影响作了评估,并通过断口分析认为。D 型石墨对基体危害较 A 型石墨小,在高 CE 下,D 型石墨是更加理想的石墨组织。     

Nano-indentation profiles of intrinsic hardness and modulus of films based on silsesquioxane modified with titanium tetrabutoxide

This study is to analyze the influence of the modifier, 5 -25 wt % titanium tetrabutoxide (TBO),on the hardness and elastic modulus of the films based on SSO deriving from hydrolytic condensation of (3-glycidoxypropyl) trimethoxysilane (GPMS) and vinyltrimethoxysilane (VMS), by the continuous stiffness measurement (CSM) technique of an instrumented-indentation testing (ⅡT) device. Films were synthesized by adding the stoichiometric amount of ethylenediamine (EDA) and benzoyl proxide (BPO) to SSO solutions in ethanol, dip-coating over glass substrates, and curing using an appropriate thermal cycle. Intrinsic values of hardness and elastic modulus were determined with the average values in “plateau region” from “four-layer”explanation. And the brittle index of the modified coating systems was analyzed.