| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 778971 | International Journal of Machine Tools and Manufacture | 2009 | 6 Pages |
Surface porosity is a common problem encountered while machining castings that contain volume porosity in the immediate subsurface. Consequent to the removal of the outer layer of the workpiece during machining, porosity that was hitherto latent in the component volume gets exposed on the generated surface in the form of a cavity. Such porosity is detrimental to the function and performance of the component with adverse cost and quality implications, if they happen to be on a bearing or sealing surface. To this end, this paper presents a novel non-contact technique that entails a pneumatic sensor for the detection of intermediate and macro-level surface porosity. The system facilitates selective inspection of surfaces including internal ones such as bore holes, and is inexpensive, flexible, and maintenance-free. It is further well suited for in-process monitoring in a machine tool environment as the hardware is simple enough for direct integration into a cutting tool holder, and the air jet cleans the inspected surface thus rendering it insensitive to cutting fluid and machining debris. The sensor performance is characterized in terms of supply pressure, stand-off distance, porosity size and speed of the inspected surface. The capability of the system for in-process application is demonstrated.
