Inter-American Materials Research - Phase Contrast in Pulsed Phase Thermography: Analytical Analysis - CIAM

美洲材料研究合作组织（Inter-American Materials Research Collaboration in Materials，CIAM）2004-2007年，我们与哥伦比亚的同一合作伙伴获得了CIAM流动补助金。这使得我们的实验室之间能够进行交流，并导致成功的研究，从而开辟了新的机会，如目前的提案。热无损评价（TNDE）是用于材料检测的NDE方法之一，沿着其他技术，如X射线，超声波等。TNDE具有独特的优势，如快速检测宽表面的可能性，它是非接触的，无害的，只需要从一侧进入零件等。然而，- 与其他无损检测方法一样-它受到几个问题的困扰，例如对噪声的高敏感性（例如来自背景的寄生反射，表面发射率的局部变化）和非均匀加热（需要热刺激来获得部件的热响应，从而能够检测表面下缺陷，因为它们相对于完好材料的响应不同）。该提案的目的是利用我们哥伦比亚合作伙伴在热四极方法方面的专业知识，帮助解决与TNDE相关的一些问题。- 目标#1：获得相位对比的分析定义（已知相位对比对于缺陷评估是稳健的，因此值得研究）。- 目标#2：建立一种方法来定位适合于计算相位对比的声音区域。相位对比的分析定义的可用性将使其值的外推在初始热脉冲加热后的红外图像中的任何地方，因此相位对比的理论值和实验热测量之间的联系是可能的，因为试样上的任何位置成为一个无声的区域。从简单参数的TNDE数据反演也成为可能。- 目标#3：包括HQP（高素质人员）培训和发展。由于我们的哥伦比亚伙伴具有专门知识，与其合作至关重要。此外，还包括一名西班牙合作伙伴，该合作伙伴对该提案具有适当的专门知识。我们的合作是协同的。

Inter-American Materials Research Collaboration in Materials (CIAM). In 2004-2007 we obtained a CIAM Mobility Grant with the same partner in Colombia. This enabled exchanges between our laboratories and led to successful research which opened new opportunities such as the current proposal. Thermal Non Destructive Evaluation (TNDE) is one of the NDE methods used for materials inspection along with other techniques such as X-Rays, Ultrasonics, etc. TNDE has unique advantages such as the possibility to inspect wide surfaces rapidly, it is non-contact, not harmful, requires access to the part from one side only, etc. However, - as other NDE methods - it is afflicted by several problems such as a high sensitivity to noise (for instance spurious reflections from the background, local variations of surface emissivity) and non-uniform heating (heat stimulation is required to get thermal response of the part and thus capability to detect subsurface defects because of their different response with respect to sound material). The objectives of this proposal is to take advantage of the expertise of our Colombian partner specialized in thermal quadrupole method to help solving some of the problems associated with TNDE. Our objectives are thus three-fold: - Objective #1: Obtain an analytical definition of phase contrast (phase contrast is known to be robust for defect assessment and thus is interesting to study). - Objective #2: Establish a method to locate a sound area suitable to compute the phase contrast. The availability of the analytical definition of phase contrast would enable the extrapolation of its value anywhere in the infrared image after the initial thermal pulse heating and thus a link between the theoretical values of the phase contrast and the experimental thermal measurements is possible since any location on the specimen becomes a sound-free area. TNDE data inversion from simple parameters thus becomes possible also. - Objective #3: HQP (Highly Qualified Personnel) training and development is included. Collaboration with our Colombian partner is essential due to its expertise. A partner from Spain with appropriate expertise for the proposal is also included. Our mutual collaboration is synergistic.