Terza cylinder rosette nickel-plated for combination sleeve

Polyamide is a thermoplastic and therefore has long, thread-like macromolecules that have no mutual crosslinking points. PA is milky white, has a slippery and abrasion-resistant surface, is resistant to chemicals and solvents, and is hard and tough. Various standards regulate mechanical connecting elements made of plastic (screws, nuts, washers), such as: B. DIN EN 34810, DIN 34811, DIN 34812, DIN 34813, DIN 34814, DIN 34815 and DIN 34816 their properties.

Nickel coatings are produced either by electroplating in accordance with DIN EN ISO 4526 or by chemical processes in accordance with DIN EN ISO 4527. In the case of electroplating, there is a risk of hydrogen embrittlement in fasteners with a hardness exceeding 390 HV. This necessitates specific measures (such as annealing), although these do not provide a 100 per cent guarantee against embrittlement.