Inadequate weld reinforcement 未填满is an area of a weld where the thickness of weld metal deposited is less than the thickness of the base material. It is very easy to determine by radiograph if the weld has inadequate reinforcement, because the image density in the area of suspected inadequacy will be more (darker) than the image density of the surrounding base material.
Excess weld reinforcement 增强余高is an area of a weld, which has weld metal added in excess of that specified by engineering drawings and codes. The appearance on a radiograph is a localized, lighter area in the weld. A visual inspection will easily determine if the weld reinforcement is in excess of that specified by the individual code involved in the inspection.
Cracking 裂纹can be detected in a radiograph only the crack is propagating in a direction that produced a change in thickness that is parallel to the x-ray beam. Cracks will appearas jagged and often very faint irregular lines. Cracks can sometimes appearing as \
Discontinuities in TIG welds
The following discontinuities are peculiar to the TIG welding process. These
discontinuities occur in most metals welded by the process including aluminum and stainless steels. The TIG method of welding produces a clean homogeneous weld which when radiographed is easily interpreted.
Tungsten inclusions. 夹钨Tungsten is a brittle and inherently dense material used in the electrode in tungsten inert gas welding. If improper welding procedures are used, tungsten may be entrapped in the weld. Radiographically, tungsten is more dense than aluminum or steel; therefore, it shows as a lighter area with a distinct outline on the radiograph.
Oxide inclusions 夹氧化物are usually visible on the surface of material being welded (especially aluminum). Oxide inclusions are less dense than the surrounding materials and, therefore, appear as dark irregularly shaped discontinuities in the radiograph.
Discontinuities in Gas Metal Arc Welds (GMAW)
The following discontinuities are most commonly found in GMAW welds.
Whiskers are short lengths of weld electrode wire, visible on the top or bottom surface of the weld or contained within the weld. On a radiograph they appear as light, \like\
Burn through (icicles) results when too much heat causes excessive weld metal to penetrate the weld zone. Lumps of metal sag through the weld creating a thick globular condition on the back of the weld. On a radiograph, burn through appears as dark spots surrounded by light globular areas.
welld-02 (Incomplete Root Fusion、根部未熔合)
welld-03 (Insuffucient Reinforcement、增强高)