Constant-depth scratch test for the quantification of interfacial shear strength at film-substrate interfaces
April 11, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesMethod for nondestructive testing of coating adhesion Method for evaluating smooth surfaces Apparatus for measuring an adhesion force of a thin film Method and apparatus for assessing surface roughness Device for measuring adhesive strength and shear strength of coated film Measurement of interfacial strength of a composite material Scratch measurement apparatus and method Patent #: 5283642 InventorsApplicationNo. 422725 filed on 04/11/1995US Classes:73/150A, Bond strength73/81, By penetrator or indentor73/866TESTING OF MATERIALExaminersPrimary: Chilcot, RichardAssistant: Noori, Max Attorney, Agent or FirmInternational ClassG01N 003/34AbstractA Constant-Depth Scratch Test (CDST) technique to quantitatively determine he shear strength of interfaces between thin metallic or non-metallic films and metal or ceramic substrates is revealed. The test overcomes two problems associated with other types of scratch tests, namely the instrumental complexity required for real-time detection of interfacial failure, and the inability to quantify interfacial strength. These problems are circumvented by maintaining a constant depth during scratching through the coating and the substrate, monitoring the horizontal and vertical forces to sustain the constant depth scratch, and finally by using a model to analyze the test results to quantify the interfacial shear strength. Unlike other scratch tests, this test is capable of measuring interfacial shear strength as a function of position on the film-substrate sample. | |
