Self Drilling Screws, 1/4-20 x 1-1/8″ Teks Select™, Hex Washer, Hex-Unslotted: TEK-1124000

Teks Select features selective hardening. When dissimilar metals (for example, aluminum and steel) are mechanically fastened, and water (from moisture or other sources) is present, galvanic corrosion occurs. This releases atomic Hydrogen. The presence of Hydrogen creates the specific conditions in which the Hydrogen assisted stress corrosion cracking (HASCC) or Hydrogen embrittlement of the fasteners may occur. If the fastener material is ductile enough, this situation is prevented. Teks Select’s selective hardening process produces drill points and lead threads hard enough (HRC 52 minimum) to drill and tap through metals. The load-bearing area remains soft enough (HRC 28-34) to remain ductile, accommodating the expansion coefficients of dissimilar metals and resisting Hydrogen embrittlement. And that means the integrity of the connection between the fastened metals is maintained over the life of the building, and the building requires less fastener maintenance.