Toughening of chemically-vapor deposited diamond by means of active incorporation of carbon allotropes

通过主动掺入碳同素异形体来增韧化学气相沉积金刚石

• 批准号: 11650075
• 负责人: KAMIYA Shoji
• 金额: $ 2.37万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11650075/
• 关键词: CVD diamond; Non-Diamond Carbon; Thin Films; Adhesive Strength; Substrate Bias; Crystalline structure; Toughening

This research project aimed at toughening of chemically-vapor deposited (CVD) diamond by means of actively incorporating carbon allotropes besides diamond. We studied the following two points and have succeeded to develop CVD diamond with adhesive toughness more than twice as much as that of usual one.Elucidation and control for the toughening mechanism by means of the incorporation of non-diamond carbon allotropes The relations between deposition condition and crystalline structure, and between crystalline structure and strength were examined for the case of CVD diamond deposited under various conditions. As a result, it is for the first time clarified that non-diamond carbon concentrates on the grain boundaries which results in weaker strength of grain boundaries than that of grains, and that selective fracture of grain boundary dissipates the energy which leads to a higher adhesive toughness for the case of the adequate grain size. On the contrary, it was confirmed that toughness of CVD diamond films monotonically decreases with respect to the increase of non-diamond carbon with finer grain size.Realization of thin films with higher toughness by means of structure control Application of bias voltage to the substrates, which is an effective method to control the state of crystalline nuclei on the interface of CVD diamond and substrates, was studied. Together with the knowledge on the effect of deposition condition mentioned above, we examined the possibility to optimize the condition to obtain higher toughness. As a consequence, we succeeded to obtain a CVD diamond coating on tungsten carbide cutting tools with the adhesive toughness of 30 J/m^2 which is more than two times of the conventional one being currently used in industry.

本研究计画旨在借由在化学气相沉积（CVD）金刚石中主动加入碳同素异形体来强化金刚石。我们研究了以下两点，成功地研制出了附着韧性比普通金刚石提高一倍以上的CVD金刚石。通过引入非金刚石碳同素异形体来阐明和控制增韧机理。研究了在不同条件下沉积的CVD金刚石的沉积条件与晶体结构、晶体结构与强度的关系。其结果是，它是第一次澄清，非金刚石碳集中在晶界上，导致晶界强度弱于晶粒的强度，和晶界的选择性断裂耗散的能量，导致较高的粘结韧性的情况下，适当的晶粒尺寸。相反，CVD金刚石膜的韧性随着非金刚石碳含量的增加而单调下降，晶粒尺寸越细，韧性越低。通过结构控制实现高韧性薄膜的研究在衬底上施加偏压是控制CVD金刚石与衬底界面晶核状态的有效方法。结合对上述沉积条件影响的认识，我们研究了优化沉积条件以获得更高韧性的可能性。因此，我们成功地获得了CVD金刚石涂层的硬质合金刀具上的附着韧性为30 J/m^2，这是目前工业上使用的传统的两倍多。

项目成果

神谷庄司(井上昭徳,坂真澄,阿部博之): "気相合成法による炭素原子堆積に伴うシリコン基板表面の残留応力に対する分子動力学的考察"日本機械学会第12回計算力学講演会講演論文集. 99-5. 25-26 (1999)

Shoji Kamiya（Akinori Inoue、Masumi Saka、Hiroyuki Abe）：《分子动力学考虑由于气相合成碳原子沉积而导致硅基板表面残余应力》第12届日本机械工程学会计算力学会议论文集。 99-5。25-26（1999）

N.Umehara (K.Kato, M.Bai and Y.Miyake): "Effect of internal stress on CNx coating on its wear in sliding friction"Surface and Coating Technology. Vol.113. 233-241 (1999)

N.Umehara（K.Kato、M.Bai 和 Y.Miyake）：“CNx 涂层上的内应力对其滑动摩擦磨损的影响”表面和涂层技术。

S.Kamiya (A.Inoue, M.Saka and H.Abe): "A molecular dynamics study of residual stress due to chemical vapor deposition of carbon on silicon substrate surface"Proceedings of the 12th computational mechanics conference JSME. vol.99-5. 25-26 (1999)

S.Kamiya（A.Inoue、M.Saka 和 H.Abe）：“硅基板表面碳化学气相沉积引起的残余应力的分子动力学研究”第 12 届计算力学会议 JSME 论文集。

K.Kato (H.Koide and N.Umehara): "Microwear properties of carbon nitride coatings"Wear. Vol.238. 40-44 (2000)

K.Kato（H.Koide 和 N.Umehara）：“氮化碳涂层的微磨损特性”磨损。

神谷庄司(井上昭徳,坂真澄,阿部博之): "超硬合金基板上のダイヤモンドコーティングの界面じん性の評価"日本機械学会2000年度年次大会講演論文集. No.00-1,Vol.III. 213-214 (2000)

Shoji Kamiya（Akinori Inoue、Masumi Saka、Hiroyuki Abe）：“硬质合金基体上金刚石涂层界面韧性的评估”日本机械工程师学会 2000 年年会论文集，第 00-1 卷，第 III 卷。 213-214 (2000)