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1.
利用有限元方法对梯度结构聚晶金刚石复合片在制造过程中产生的残余热应力进行了计算,并分析了梯度组成分布指数及梯度层层数对热应力的影响。优化结果表明,分布指数最佳值为1.2,功能梯度层数为6层;与普通双层结构聚晶金刚石复合片相比,轴向拉应力由986 MPa降到了323 MPa,剪应力由722 MPa降到454 MPa;此外还改善了界面处的应力分布,大大提高了界面的结合强度。   相似文献   

2.
残余热应力是影响聚晶金刚石复合片(PDC)性能好坏的最重要因素之一。考虑聚晶金刚石层(PCD)与硬质合金层厚度比以及PDC压制过程中烧结温度的波动对聚晶金刚石复合片残余热应力的影响,在ANSYS中建立PDC模型,运用热-结耦合法分析PDC的残余热应力。计算表明,随着PCD层与硬质合金层厚度比由0.067增加到0.333,PCD层表面中心的压应力由1.61 GPa降低到380 MPa,PCD层最大径向压应力由1.61 GPa降低1.03 GPa左右,而PCD层边缘靠近界面附近最大轴向拉应力逐渐增大;随着PDC压制过程中烧结温度由1000℃升高到1500℃,PCD层的最大径向压应力、最大轴向拉应力以及最大剪应力等均逐渐增大。认为,在研究PDC合成新工艺过程中,应在保证PDC使用寿命的前提下尽量降低PCD层与硬质合金层厚度比;必须尽量切断原材料以及人为操作对温度的影响。   相似文献   

3.
陈萍 《探矿工程》1990,(1):59-62
国外自美国GE公司于七十年代首次合成聚晶金刚石复合片以来,聚晶金刚石及复合片的研制工艺水平又有了很大程度的提高,复合片品种形式增加了许多。本文将介绍美国、瑞典、英国、日本和苏联等国家的五种聚晶金刚石和十一种聚晶金刚石复合片及切削具的制造方法。一、五种聚晶金刚石1.硅合金浸渍的聚晶金刚石这种聚晶金刚石由美国Sii Megadiamond Inc,于1985年7月研制成功。它使用硅与Ⅷ族金属的混合粉末形式与已去掉触媒金属的聚晶金刚石一起放入六面顶或两面顶压机中制造而成。含硅混合物在高温高压  相似文献   

4.
张旭升 《地质与勘探》1990,26(10):62-63
本文简单地介绍了聚晶金刚石复合片钻头、热稳定性聚晶金刚石钻头、热稳定性聚晶金刚石镶嵌齿钻头及混合钻头等的结构特点、破岩方式和适用地层.  相似文献   

5.
考虑界面软化特性的垃圾填埋场斜坡上土工膜内力分析   总被引:2,自引:0,他引:2  
林伟岸  朱斌  陈云敏  詹良通 《岩土力学》2008,29(8):2063-2069
为分析垃圾填埋场斜坡上防渗系统中的土工膜在上覆垃圾堆体重力作用下产生的拉应力,考虑土工膜-黏土界面的应变软化特性,通过建立土工膜受力的平衡方程获得了土工膜拉应力的解析解。与传统方法相比,该方法可分析土工膜-黏土界面不同位置所处的3种应力状态:弹性状态、软化状态及残余状态,从而使得垃圾填埋场斜坡上土工膜的受力分析更为合理。参数分析显示,当软化阶段的强度损失及残余位移与峰值位移的差值较小时,土工膜-黏土界面的峰值强度对土工膜最大拉应力的影响较小,而其残余强度是主要控制因素;而当土工膜-黏土界面的软化特征较明显时,则峰值强度和残余位移的影响也更为明显。另外,土工膜上覆堆体高度、斜坡坡度及土工膜锚固长度对土工膜拉应力也有较大影响。  相似文献   

6.
2009年8月17日,由河北省地矿局地质矿产科技处组织,主管探矿科研生产的高献计副局长亲自带队的5人专家验收组,对河北省地矿局探矿技术研究院完成的三个省局下达.的探矿科研项目进行了评审验收。三个科研项目分别是:《如何提高金刚石钻头使用寿命研究》、《人造金刚石聚晶、复合片钻头研制》和《深孔绳索取心安全打捞输送器(SSD-75)研制》。  相似文献   

7.
许四法  杨杨 《岩土力学》2008,29(9):235-2354
为了评价垃圾填埋场防渗系统材料界面之间的摩擦特性以及土工合成材料端部的应力,进行了模拟试验和有限元分析。采用直接剪切试验,获得了土与短纤维无纺布、短纤维无纺布与HDPE土工膜以及短纤维无纺布与TPO(PE)界面的摩擦角和黏聚力;采用离心模拟试验,得到了伴随土压缩引起的短纤维无纺布和土工膜端部拉应力。试验结果表明:材料界面之间的摩擦角较大,但黏聚力不大;伴随填埋高度的增加,短纤维无纺布和土工膜端部的拉应力也随之增大。运用有限元对土压缩引起的短纤维无纺布和土工膜端部拉应力以及界面的摩擦应力分布进行了分析,并与试验结果进行了对比,分析结果表明:两者基本一致,碾压机械下方土工膜界面之间摩擦应力比较大。  相似文献   

8.
人造金刚石聚晶地质岩心钻头是我院从1973年以来,应用粉末冶金热压法表镶研制成功的,是金刚石地质岩心钻头的新产品。进行了大量的探索性试验,生产试验和生产应用,获得了良好的钻探效果,提高了钻探经济效益。为进一步推广应用聚晶钻头,我们总结了一套使用经验,帮助广大操作者及时掌握,将摘要介绍如下:(1)人造金刚石聚晶:又称金刚石聚合体,或称金刚石烧结体。聚晶分生长、爆炸、静压。静压聚晶是以40微米以细的人造金刚石微粉,与结合剂成分均匀混合,装入石墨模具内,置于金刚石合成压机的腔体内,经高温高压烧结而成。具有各…  相似文献   

9.
Rowl.  JC 《探矿工程译丛》1997,(1):40-41,36
化学气相沉积(CVD)金刚石薄膜的面市,为钻进岩石选用新型切削具开辟了新设计途径。其功能明显地表现在:(a)良好的均匀磨损机制;(b)高温下钻进效果好;(c)热导率高;(d)与其他材质易于形成层状结构。用碳化钨钨钴硬合金片(TC)、热稳性聚晶(TSP)、金刚石聚晶复合片(PCD)制成的多层切削具,为设计制造新式钻头提供以下功效:(a)在硬而裂隙岩石中钻进能抗冲击载荷;(b)可进行抗热设计以限制切削  相似文献   

10.
人造聚晶金刚石复合片,在七十年代已在国外被成功地运用于制造石油钻头.特别在全面钻头上,已取得了相当好的经济效果. 我国八十年代初,开始对上述复合片进行研制.首先是被成功地运用在刀具上,后来才在石油钻头上开始试验.这主要是由于石油钻井对这种磨具提出了更严格的性能要求. 1982年10月,我们对锦州碳素厂研制的人造  相似文献   

11.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

12.
Well investigated platforms have been selected in each continent, and the history of Cretaceous transgressions and regressions there is concisely reviewed from the available evidence. The factual records have been summarized into a diagram and the timing of the events correlated between distant as well as adjoining areas.On a global scale, major transgressions were stepwise enlarged in space and time from the Neocomian, via Aptian-Albian, to the Late Cretaceous, and the post-Cretaceous regression was very remarkable. Minor cycles of transgression-regression were not always synchronous between different areas. Some of them were, however, nearly synchronous between the areas facing the same ocean.Tectono-eustasy may have been the main cause of the phenomena of transgression-regression, but certain kinds of other tectonic movements which affected even the so-called stable platforms were also responsible for the phenomena. The combined effects of various causes may have been unusual in the Cretaceous, since it was a period of global tectonic activity. The slowing down of this activity followed by readjustments may have been the cause of the global regression at the end of the Cretaceous.  相似文献   

13.
The Afyon stratovolcano exhibits lamprophyric rocks, emplaced as hydrovolcanic products, aphanitic lava flows and dyke intrusions, during the final stages of volcanic activity. Most of the Afyon volcanics belong to the silica-saturated alkaline suite, as potassic trachyandesites and trachytes, while the products of the latest activity are lamproitic lamprophyres (jumillite, orendite, verite, fitztroyite) and alkaline lamprophyres (campto-sannaite, sannaite, hyalo-monchiquite, analcime–monchiquite). Afyon lamprophyres exhibit LILE and Zr enrichments, related to mantle metasomatism.  相似文献   

14.
正20140751 Guo Xincheng(Geological Party,BGMRED of Xinjiang,Changji 831100,China);Zheng Yuzhuang Determination and Geological Significance of the Mesoarchean Craton in Western Kunlun Mountains,Xinjiang,China(Geological Review,ISSN0371-5736,CN11-1952/P,59(3),2013,p.401-412,8  相似文献   

15.
正20141058 Chen Ling(Key Laboratory of Mathematical Geology of Sichuan Province,Chengdu University of Technology,Chengdu610059,China);Guo Ke Study of Geochemical Ore-Forming Anomaly Identification Based on the Theory of Blind Source Separation(Geosci-  相似文献   

16.
SEISMIC GEOLOGY     
正20141334 Chen Kun(Institute of Geophysics,China Earthquake Administration,Beijing100081,China);Yu Yanxiang Shakemap of Peak Ground Acceleration with Bias Correction for the Lushan,Sichuan Earthquake on April20,2013(Seismology and Geology,ISSN0253-4967,CN11-2192/P,35(3),2013,p.627-633,2 illus.,1 table,9 refs.)Key words:great earthquakes,Sichuan Province  相似文献   

17.
正20141624 Cai Xiongfei(Key Laboratory of Geobiology and Environmental Geology,Ministry of Education,China University of Geosciences,Wuhan 430074,China);Yang Jie A Restudy of the Upper Sinian Zhengmuguan and Tuerkeng Formations in the Helan Mountains(Journal of Stratigraphy,ISSN0253-4959CN32-1187/P,37(3),2013,p.377-386,5 illus.,2 tables,10 refs.)  相似文献   

18.
PALEONTOLOGY     
正20142263Lü Shaojun(Geological Survey of Jiangxi Province,Nanchang 330030,China)Early-Middle Permian Biostratigraphical Characteristics in Qiangduo Area,Tibet(Resources SurveyEnvironment,ISSN1671-4814,CN32-1640/N,34(4),2013,p.221-227,2illus.,2tables,22refs.)Key words:biostratigraphy,Lower Permian,Middle Permian,Tibet  相似文献   

19.
正20142560Hu Hongxia(Regional Geological and Mineral Resources Survey of Jilin Province,Changchun 130022,China);Dai Lixia Application of GIS Map Projection Transformation in Geological Work(Jilin Geology,ISSN1001-2427,CN22-1099/P,32(4),2013,p.160-163,4illus.,2refs.)  相似文献   

20.
GEOCHEMISTRY     
正20140692 Duo Tianhui(No.402 Geological Team,Exploration of Geology and Mineral Resources of Sichuan Authority,Chengdu611730,China);Wang Yongli Computer Simulation of Neptunium Existing Forms in the Groundwater(Computing Techniques for Geophysical and Geochemical Exploration,ISSN1001-1749,CN51-1242/P,35(3),  相似文献   

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