The radioisotope used in industrial radiography for the rapid checking of faults in welds and casting is

The radioisotope used in industrial radiography for the rapid checking of faults in welds and casting is cobalt-60. Cobalt-60 is a radioactive isotope that emits gamma rays, which are high-energy electromagnetic radiation. These gamma rays can penetrate through solid materials such as metal and concrete, allowing technicians to see the internal structure of the material without having to physically cut it open. This makes it ideal for checking faults in welds and castings, as it can quickly reveal any cracks or voids that might otherwise be difficult to detect. Once the radiography is done, the cobalt-60 source is removed and the material is safe to handle. The use of cobalt-60 in industrial radiography is a well-established and widely used technique that has been safely and effectively used for many decades.