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Radiographic testing is a nondestructive detection method of inspecting materials for internal flaws by using short wavelength electromagnetic radiation to penetrate various materials and using radiographic film as recording medium and show paths. Radiographic testing takes full advantage of various characteristics of X-rays and γ-rays, such as the refractive index of X-rays and γ-rays close to 1, X-rays and γ-rays both have strong penetrating power, they only produce diffraction and interference phenomena in the crystal grating, they can have fluorescence effect, ionization effect, thermal and chemical effects on some materials, easier attenuation and other characteristics. The specimen to be inspected is placed between the source of radiation and the detecting device, usually the film in a light tight holder or cassette, and the radiation is allowed to penetrate the part for the required length of time to be adequately recorded.

Radiographic testing mainly uses X-rays and γ-rays. X-ray, also known as roentgen rays, is a form of electromagnetic radiation. X-ray wavelengths are longer than those of gamma rays. Due to its penetrating ability, it is widely used to image the inside of objects, such as in medical radiography and airport security. X-rays can increase the risk of developmental problems and cancer,and are classified as a carcinogen by both the World Health Organization's International Agency for Research on Cancer and the U.S. government. Gamma rays are ionizing radiation, and are thus biologically hazardous. Low levels of gamma rays cause a stochastic health risk, which for radiation dose assessment is called the probability of cancer induction and genetic damage. High doses produce certainty effects, which is the severity of acute tissue damage that is bound to happen.

Tungsten alloy shielding can effectively shield the radiation generated during the process of radiographic testing. Compared to traditional radiation shielding materials(such as lead), tungsten alloy radiation shielding provide excellent density with small capacity. At the same weights high density alloy can provide the same energy absorption as lead using 1/3 less material. And tungsten alloy will not pollute the environment.