EFFECT OF BAKING ON AEROSPACE GRADE ELECTROPLATED ZN AND CD COATING ON HIGH STRENGTH STEEL SUBSTRATES - A CORRELATIVE STUDY OF MECHANICAL STRENGTH WITH HYDROGEN CONTENT

摘要

Regulation on Cd coating and large electrode potential difference between Zn and steel has led to development of new sacrificial coating like Zn-Ni, Zn-Fe, Zn-Al, Zn-Co coatings. To evaluate these potential new coatings for hydrogen embrittlement of substrate after plating and its removal by baking, a baseline of mechanical properties with Cd and Zn coating must be defined. Incremental step load testing (ISL) coupled with Thermal Desorption Spectroscopy (TDS) is used to correlate average fracture load with the hydrogen content in the notch bar. Standard F1940 and F519 le high strength steel notch bars are used to study the effect of baking, acid pickling and notch root radius on average fracture load.