用EBSD删除序列号的法医重建
Here, we demonstrate the ability of EBSD to detect otherwise invisible plastic deformation introduced to the sample by the engraving process – allowing the reconstruction of a polished away serial number.
Sometimes, during a crime, keys or other metallic objects such as guns which are identifiable by a serial number are used. When this happens, a common approach utilised by criminals to try and avoid detection is to attempt to destroy the serial number by scratching it off. This can destroy on otherwise useful line of evidence meaning that the forensic examiner or law enforcement agency has to search for alternative means to solve the crime. However, there is a way to recover it...
当序列号印在金属物体上时,它会导致该金属结构中断到大于实际印记深度的深度。当有人试图刮掉那个序列号时,他们通常只能通过眼睛不再可见。
EBSD能够看到否则否则是隐形的东西 - 甚至到显微镜中成像的其他方法 - 以及图像据信被摧毁的序列号。
This works by looking at the contrast present in the diffraction patterns when the sample is mapped by EBSD. The more deformed a particular point is, the lower the contrast will be. By making an image showing the level of contrast at each point, we can visualise the original serial number.
Back to Forensics & EnvironmentHere, we demonstrate the ability of EBSD to detect otherwise invisible plastic deformation introduced to the sample by the engraving process – allowing the reconstruction of a polished away serial number.