Name: intermediate strain rate material characterization with digital image correlation
Uploaded: 2019-03-01T14:00:00
Description: Watch this Scientific Journal Video about Intermediate Strain Rate Material Characterization with Digital Image Correlation at JoVE.com

提交人承认 d买卖部、michel delonyy、tyler musclow、fraser kirby、joshua ilse 和 alex naftel 提供的巨大帮助。还感谢加拿大国家研究理事会 (nrc) 通过安全材料技术 (smt) 方案提供的财政支持。

1. 样品制备
<ol><li>根据 iso 标准6提前准备犬骨形状的拉伸试样。 注: 也使用类似的样品4。</li>
	<li>在拉伸试样的选项卡部分 (负载测量必须) 和仪表部分 (应变测量可选) 上安装应变片。<ol>
<li>根据应变片的尺寸、最大扩展、测试温度、电阻等选择合适的应变片型号4。</li>
		<li>用异丙醇清洁试样表面, 以消除任何污染, 并将应变片安装在适当?...

<ol>
	<li>Xiao, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+tensile+testing+of+plastic+materials.">Dynamic tensile testing of plastic materials.</a> Polymer Testing. 27 (2), 164-178 (2008).</li><li>Nemat-Nasser, S., Isaacs, J. B., Starrett, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hopkinson+techniques+for+dynamic+recovery+experiments.">Hopkinson techniques for dynamic recovery experiments.</a> Proceedings of Royal Society of London A Mathematical Physical and Engineering Sciences. 435 (1894), 371-391 (1991).</li><li>Bruce, D., Matlock, D., Speer, J., De, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+the+strain-rate+dependent+tensile+properties+of+automotive+sheet+steels.">Assessment of the strain-rate dependent tensile properties of automotive sheet steels.</a> SAE World Congress. , (2004).</li><li>Rahmat, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+mechanical+characterization+of+aluminum:+analysis+of+strain-rate-dependent+behavior.">Dynamic mechanical characterization of aluminum: analysis of strain-rate-dependent behavior.</a> Mechanics Time-Dependent Materials. , (2018).</li><li>Gray, G., Blumenthal, W. 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B., Martinez-Rubi, Y., Simard, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+Mechanical+Characterization+of+Boron+Nitride+Nanotube+-+Epoxy+Nanocomposites.">Dynamic Mechanical Characterization of Boron Nitride Nanotube - Epoxy Nanocomposites.</a> Polymer Composites. , (2018).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SAE,+High+strain+rate+testing+of+polymers.">SAE, High strain rate testing of polymers.</a> SAE International. , 27 (2008).</li><li>Wang, Y., Xu, H., Erdman, D. L., Starbuck, M. J., Simunovic, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+high-strain+rate+mechanical+behavior+of+AZ31+magnesium+alloy+using+3D+digital+image+correlation.">Characterization of high-strain rate mechanical behavior of AZ31 magnesium alloy using 3D digital image correlation.</a> Advanced Engineering Materials. 13 (10), 943-948 (2011).</li><li>Mansilla, R. A., Garc&#237;a, D., Negro, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+tensile+testing+for+determining+the+stress-strain+curve+at+different+strain+rate.">Dynamic tensile testing for determining the stress-strain curve at different strain rate.</a> 6th International Conference on Mechanical and Physical Behaviour of Materials Under Dynamic Loading. 10 (9), 695-700 (2000).</li><li>Zhu, D., Mobasher, B., Rajan, S. D., Peralta, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+Dynamic+Tensile+Testing+Using+Aluminum+Alloy+6061-T6+at+Intermediate+Strain+Rates.">Characterization of Dynamic Tensile Testing Using Aluminum Alloy 6061-T6 at Intermediate Strain Rates.</a> Journal of Engineering Mechanics. 137 (10), 669-679 (2011).</li><li>Schossig, M., Bieroegel, C., Grellmann, W., Bardenheier, R., Mecklenburg, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+strain+rate+on+mechanical+properties+of+reinforced+polyolefins.">Effect of strain rate on mechanical properties of reinforced polyolefins.</a> 16th European Conference of Fracture. , 507-508 (2006).</li><li>Xia, Y., Zhu, J., Wang, K., Zhou, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+verification+of+a+strain+gauge-based+load+sensor+for+medium-speed+dynamic+tests+with+a+hydraulic+test+machine.">Design and verification of a strain gauge-based load sensor for medium-speed dynamic tests with a hydraulic test machine.</a> International Journal of Impact Engineering. 88, 139-152 (2016).</li><li>Yang, X., Hector, L. G., Wang, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Combined+Theoretical/Experimental+Approach+for+Reducing+Ringing+Artifacts+in+Low+Dynamic+Testing+with+Servo-hydraulic+Load+Frames.">A Combined Theoretical/Experimental Approach for Reducing Ringing Artifacts in Low Dynamic Testing with Servo-hydraulic Load Frames.</a> Experimental Mechanics. 54 (5), 775-789 (2014).</li><li>Xia, Y., Zhu, J., Zhou, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Verification+of+a+multiple-machine+program+for+material+testing+from+quasi-static+to+high+strain-rate.">Verification of a multiple-machine program for material testing from quasi-static to high strain-rate.</a> International Journal of Impact Engineering. 86, 284-294 (2015).</li><li>Yan, B., Kuriyama, Y., Uenishi, A., Cornette, D., Borsutzki, M., Wong, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recommended+Practice+for+Dynamic+Testing+for+Sheet+Steels+-+Development+and+Round+Robin+Tests.">Recommended Practice for Dynamic Testing for Sheet Steels - Development and Round Robin Tests.</a> SAE International. , (2006).</li><li>Borsutzki, M., Cornette, D., Kuriyama, Y., Uenishi, A., Yan, B., Opbroek, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recommendations+for+Dynamic+Tensile+Testing+of+Sheet+Steels.">Recommendations for Dynamic Tensile Testing of Sheet Steels.</a> International Iron and Steel Institute. , (2005).</li><li>Rusinek, A., Cheriguene, R., B&#228;umer, A., Klepaczko, J. 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H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+hybrid+Technique+for+compression+testing+at+intermediate+strain+rates.">A hybrid Technique for compression testing at intermediate strain rates.</a> Experimental Techniques. 20 (5), 21-24 (1996).</li><li>Xiao, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+dynamic+tensile+testing.">Analysis of dynamic tensile testing.</a> 11th International Congress and Exhibition on Experimental and Applied Mechanics. , (2008).</li><li>Othman, R., Gu&#233;gan, P., Challita, G., Pasco, F., LeBreton, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+modified+servo-hydraulic+machine+for+testing+at+intermediate+strain+rates.">A modified servo-hydraulic machine for testing at intermediate strain rates.</a> International Journal of Impact Engineering. 36 (3), 460-467 (2009).</li><li>Kwon, J. 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从实验中获得的原始数据受试样几何形状和应变片在试样上的位置的影响。在较高应变速率下, 压电负载垫圈在负载框架中获得的低应变率动态测试中的负载数据 (bruce等人).建议>, 而王等人则建议。9报告此限制为 100/) 通常由于与加载相关的动态波而受到较大的振幅振荡。如图 1所示, 由于噪声水平高, 试样材料、?...

大多数材料在其力学行为1中都显示出一定程度的应变率依赖性, 因此, 仅在准静态应变速率下进行的机械测试不适合确定动态的材料性能应用。通常使用五种类型的机械测试系统来研究材料的应变率依赖性: 传统的螺杆驱动负载框架、伺服液压系统、高速伺服液压系统、冲击测试仪和 hopkinson 杆系统1. 在过去50年里, 拆分的 hopkinson 条一直是材料动态表征的共同设施 2。还努力修改 hopkinson 柱, 以中等和较低的应变率进行测试。然而, 这些设施通常更适合于材料的高应变率特征 (即通常大于 200s)。在10−200/s 范围内 (即从拆分 hopkinson 3 获得的准静态和高应变率结果) 中, 关于材料性能的应变率特征存在差距 (即从拆分 hopkinson 3 获得的准静态应变率和高应变率结果), 这是由于进入设施的机会有限, 缺乏可靠的中间应变率材料测试程序。
高速伺服液压负载框架以恒定和预定义的速度将载荷施加到试样上。这些负载框架受益于松弛适配器, 在拉伸试验中, 该适配器允许横梁在加载开始前达到所需的速度。松弛适配器允许头部在一定距离 (例如0.1 米) 内行驶, 以达到目标速度, 然后开始将载荷施加到试样上。高速伺服液压负载框架通常在位移控制模式下进行测试, 并保持恒定的执行器速度, 以产生恒定的工程应变速率3。
测量试样伸长率的技术一般分为接触技术或非接触技术4。接触技术包括使用夹式扩展器等仪器, 而激光扩展器则用于非接触式测量。由于接触扩展器容易受到惯性的影响, 因此不适合动态测试;非接触式扩展器不会受到此问题的影响。
数字图像相关性 (dic) 是一种光学、非接触式、全场应变测量技术, 是一种用于应变测量的替代方法, 用于测量应变载荷并克服与之相关的一些挑战 (例如, 响铃现象)。动态材料特性5。电阻应变片可能会受到一些限制, 例如测量范围有限、伸长率范围有限和安装方法有限, 而 dic 始终能够在测量过程中从试样表面提供全场应变测量。实验。
所介绍的程序描述了使用高速伺服液压负载框架与 dic 一起, 并可作为补充文件, 以澄清最近制定的标准准则6 , 以澄清实验过程的细节。伺服-液压载荷框架上的部分可以遵循各种测试设置 (例如, 拉伸、压缩和剪切), 甚至可以使用普通的准静态载荷框架, 因此涵盖了广泛的设施。此外, dic 部分可单独应用于任何类型的机械或热测试, 但只需稍作修改。

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	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:280px;">Camera Lens</td>
			<td style="width:183px;">Opto Engineering</td>
			<td style="width:175px;"></td>
			<td style="width:167px;">Telecentric lens 23-64</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:280px;">High Speed Camera&#160;</td>
			<td style="width:183px;">SAX Photron Fastcam&#160;</td>
			<td style="width:175px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:280px;">High Speed DAQ&#160;</td>
			<td style="width:183px;">National Instruments</td>
			<td style="width:175px;">USB-6259</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:280px;">High Speed Servo-Hydraulic Load Frame</td>
			<td style="width:183px;">MTS Systems Corporation</td>
			<td style="width:175px;">Custom Built</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:280px;">Jab Bullet Light with diffuser&#160;</td>
			<td style="width:183px;">AADyn JAB BULLET&#160;</td>
			<td style="width:175px;"></td>
			<td style="width:167px;">&#160;15&#176; diffusers&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:280px;">Strain gauge</td>
			<td style="width:183px;">Micro-Measurements</td>
			<td style="width:175px;">Model EA-13-062AQ-350</td>
			<td style="width:167px;"></td>
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	</tbody>
</table>

intermediate strain rate material characterization with digital image correlation

材料在动态载荷作用下的机械响应通常不同于在静态条件下的行为;因此, 用于材料表征的常用准静态设备和程序不适用于动态载荷下的材料。材料的动态响应取决于其变形率, 大致分为高 (即大于 200s)、中间 (即 10−200/s) 和低应变率 (即小于 10/)。每一种制度都要求有具体的设施和测试协议, 以确保所获得数据的可靠性。由于使用高速伺服液压设备和经过验证的测试协议的机会有限, 在中间应变速率下, 结果存在明显差距。目前的手稿提出了一个验证的协议, 在这些中间应变速率的不同材料的表征。应变计仪器和数字图像相关协议也包括作为免费模块, 从每一个测试中提取最高水平的详细数据。介绍了从各种材料和试验装置 (如拉伸和剪切) 获得的原始数据的实例, 并介绍了用于处理输出数据的分析程序。最后, 讨论了使用现行协议进行动态表征的挑战, 以及设施的局限性和克服潜在问题的方法。

动态测试的持续时间通常与应力波在负载列车 (即夹具、试样和载荷) 系统1的长度上往返所需的时间相当。如果在动态试验中控制应力波的数量和振幅, 以实现动态平衡, 并且试样在几乎恒定的应变速率下经历均匀变形, 则动态试验是有效的。汽车工程师协会 (sae) sae j2749 标准8要求在试样屈服点之前至少有10个弹性反射波通过试样测量长度...

Watch this Scientific Journal Video about Intermediate Strain Rate Material Characterization with Digital Image Correlation at JoVE.com

Intermediate Strain Rate Material Characterization with Digital Image Correlation

本文提出了一种利用高速伺服-液压载荷框架对中间应变率拉伸试样进行动态表征的方法。还定义了应变计检测和分析的程序, 以及样品上的数字图像相关应变测量程序。

数字图像相关的中间应变率材料表征

The mechanical response of a material under dynamic load is typically different than its behavior under static conditions; therefore, the common ...

材料的机械性能取决于负载应用速率。我们的协议可用于以中等应变速率捕获材料行为。该技术的主要优点是，使用非接触式全场应变测量技术，使用高速摄像机捕获表面应变时，可以描述材料。材料的中间应变速率表征通常需要处理结果中称为振铃的不良振荡，通过适当的试样设计和测试方案避免。在开始手术之前，根据国际标准化组织的参数准备狗骨形拉伸标本。接下来，绘制试样表面以显示高对比度特征。将对比度模式与相机图像传感器大小相匹配，例如每个暗对比度特征由大约三个像素或更多组成，然后将试样放在一边，让油漆干燥。当试样准备就绪时，打开控制台的电源，并确认隔离阀（从泵到高速率框架）已打开，然后再打开计算机。从桌面启动控制器应用程序，选择高速率计算位移 cfg 配置，然后单击重置，以清除联锁一。启动液压泵，一次打开一个维修歧管，等待低指示灯停止闪烁，然后按每个歧管的高指示器。启动测试设计软件，确认液压泵和高维修歧管已打开。然后单击、文件、新测试、模板和自定义模板测试，然后选择张力测试。对于应变片的设置，将负载框架交叉头控制开关设置为低速率，并根据导线颜色将试样应变片的导线与试验室内应变箱的导线匹配。然后，在控制器应用程序中，在辅助输入和应变1下，选择应变的最大范围。接下来，激活手动控制，并在负 125 毫米时将头部的位置输入到完全扩展的位置。关闭启用手动命令复选框，并取消选中独占控制框。弹性线可用于将松弛适配器保持回缩位置，为安装优惠券提供空间。使用安装夹具将息票对齐在手柄内。按按键图标激活听筒，并确认软件中的独占控制盒未选中。确保顶部夹具松动，以防止对试样产生不良负载应用，并拆下弹性线。按下车轮图标以激活控制器，然后缓慢滚动车轮以将头向下，直到松弛适配器的底部臂几乎完全缩回。再次按按键图标，停用听筒并使用手动控制检查专属控制盒，使头部正好为负 125 毫米。使用扳手和钥匙旋转松弛适配器，在不扭曲息票的情况下拧紧顶部夹具，并检查松弛适配器和中间交叉头之间的螺旋垫圈，以确保垫圈紧固，并且负载列车上没有轴向间隙。然后，将机架返回到高速率，并确保机柜门紧闭。要设置数字图像相关性的仪器，请打开高速成像查看器软件，然后单击检测，然后再保存设置。单击相机选项并选择输入输出选项卡以设置外部信号。要设置帧速率和帧分辨率，请单击变量，将摄像机频率和数据采集框采集速率设置为与负载帧中的高速数据采集系统相同的数字。然后，在高速成像查看器中打开高速数据采集，并选择每帧所需的通道和样本。若要运行测试，请打开张力测试并选择新的测试运行以输入有效的文件名。根据需要修改字段，然后单击"确定"。对于斜坡速率，选择标称所需的头速度，然后单击"确定"。将出现一系列提示，提醒应检查关键硬件，然后可以通过单击运行图标启动测试。在控制台上，按住臂充电蓄能器开关以武装系统。然后，按火完成测试。测试速度应基于真实场景进行计算，例如，可以应用约 8 米/秒的车祸模拟速度。对于数据分析，请将负载帧计算机的原始数据导出到选择的后处理软件中，并确定试样失败的仪表部分上的位置。将应变场限制在故障区附近的局部区域，并测量和记录局部区域的应变。然后，绘制从测量中获得的应力应变曲线。这两项测试都执行得当，但直接从负载框架力链路中提取的负载数据不能用于替代负载测量技术（如标签节应变测量）中。但是，在此测试中，负载帧的原始负载数据与应变片负载非常一致。显示了狗骨铝标本的数字图像相关结果的典型示例，该样本与整个仪表部分的时间应变场演化。试样给定横截面内的均匀应变说明了在测试期间的正确装载和数据分析。而上一张图像中数字图像相关性的丧失是由于严重的脖子，导致油漆剥落，在故障区附近发生故障之前是不可避免的。这些应力应变曲线从数字图像相关性和负载帧交叉头位移数据中获得，说明整个仪表部分的平均应力应变，并论证了该技术的有效性和结果之间的良好一致。对结果进行全面评估可确保协议在有效假设的边界内执行。如惯性主导制度或防滑条件和抓地力。按照此过程，可以在各种材料上执行一系列不同的机械特性测试，如纯粹的、弯曲、穿刺或压缩测试。该技术填补了准静态试验和超高应变率表征技术之间的空白。使我们能够将材料行为完全描述为应变速率的函数。

Research

Education

JoVE Core

JoVE Journal

Mechanical Engineering

Engineering

Unit 1

Stress and Strain - Axial Loading

SCIENTISTS IN ACTION

Echo Particle Image Velocimetry

回声粒子图像测速技术

The transport of mass, momentum, and energy in fluid flows is ultimately determined by spatiotemporal distributions of the fluid velocity field.1 ...

科研

工程学

High-resolution, High-speed, Three-dimensional Video Imaging with Digital Fringe Projection Techniques

Digital fringe projection (DFP) techniques provide dense 3D measurements of dynamically changing surfaces.&#160;Like the human eyes and brain, DFP uses ...

Characterization of Full Set Material Constants and Their Temperature Dependence for Piezoelectric Materials Using Resonant Ultrasound Spectroscopy

全套材料常数表征及其温度依赖性的压电材料使用共振超声波谱

During the operation of high power electromechanical devices, a temperature rise is unavoidable due to mechanical and electrical losses, causing the ...

Experimental Methods for Investigation of Shape Memory Based Elastocaloric Cooling Processes and Model Validation

基于形状记忆调查Elastocaloric冷却过程和模型验证实验方法

Shape Memory Alloys (SMA) using elastocaloric cooling processes have the potential to be an environmentally friendly alternative to the conventional vapor ...

Compact Lens-less Digital Holographic Microscope for MEMS Inspection and Characterization

紧凑的镜头少数字全息显微镜的MEMS检测与表征

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and ...

Emission Spectroscopic Boundary Layer Investigation during Ablative Material Testing in Plasmatron

烧蚀材料在试验过程中等离子体发生器发射光谱边界层研究

Ablative Thermal Protection Systems (TPS) allowed the first humans to safely return to Earth from the moon and are still considered as the only solution ...

Strain Sensing Based on Multiscale Composite Materials Reinforced with Graphene Nanoplatelets

基于多尺度复合材料的增强与石墨烯纳米片应变传感

The electrical response of NH2-functionalized graphene nanoplatelets composite materials under strain was studied. Two different manufacturing methods are ...

Carrier Lifetime Measurements in Semiconductors through the Microwave Photoconductivity Decay Method

微波导光衰减法测量半导体中的载波寿命

This work presents a protocol employing the microwave photoconductivity decay (&#956;-PCD) for measurement of the carrier lifetime in semiconductor ...

Full-field Strain Measurements for Microstructurally Small Fatigue Crack Propagation Using Digital Image Correlation Method

基于数字图像相关的微结构小疲劳裂纹扩展的全场应变测量

A novel measurement approach is used to reveal the cumulative deformation field at a sub-grain level and to study the influence of microstructure on the ...

Production of a Strain-Measuring Device with an Improved 3D Printer

使用改进的 3D 打印机生产应变测量设备

A traditional strain measurement sensor needs to be electrified and is susceptible to electromagnetic interference. In order to solve the fluctuations in ...