Impact strength weldability

Somewhat between PTFE and PFA materials is the product Hostaflon TFM, which is a copolymer of TFE and a small amount of the perfluoro(propyl vinyl ether). It has improved impact strength and weldability and has been promoted as a suitable material for forming into bottles. Yet another TFE-perfluoroalkoxy copolymer was introduced by Du Pont in 1979 as Teflon EPE. This material had a somewhat lower melting point (295 °C) than the more common PFA fluoropolymers but it is no longer marketed. 

The 2519 Al alloy is an impact-resistant aluminum alloy, potentially for armor applications the 7050 Al alloy is a high-strength nonweld-able Al-Cu-Zn alloy of particular interest for aircraft applications and the moderate-strength, weldable 6061 Al alloy is a versatile, commonly used aluminum alloy. Room-temperature form-ability results following FSP are presented as follows for these three alloys. 

Throughout the world, many arc welding methods are used to fabricate large-capacity structures from these steels. The weldability of both steels was evaluated using various methods of welding. Thin samples of both steels were satisfactorily welded. Nevertheless, weld metal of the same composition was susceptible to pore and hot crack formation and resulted in decreased ductility and low impact strength at low temperatures. Both steels were sensitive to the welding heat effect this was... 

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