There are at present little or limited long term creep data that can be found in the literature for modified 9Cr. This is partly due to the relatively recent development of the alloy and partly due to data not being in the public domain. (W 30) (1)

Long term = Longo prazo

The attempts to work at high vacuum, although reasonably successful in the short term, were eventually derailed by inconsistent sealing and pumping performance. (W 72) (2)

Short term = Curto prazo

Welding of space and aircraft structures is increasingly becoming a reality, helped by the development of friction stir welding……… Future welded aircraft may become a medium term reality with the exploitation of this process for wing and fuselage structures. Most airframe manufacturers are now actively developing the technology with TWI. (Welding 272) (3)

Medium term = Médio prazo

(1) Creep Crack Growth Prediction of Very Long Term P91 Steel Using Extrapolated Short-Term Uniaxial Creep DataS. Maleki TWI LtdA. Mehmanparast, K. M. Nikbin Imperial College London.Paper presented at the 2013 ASME Pressure Vessels and Piping Conference. Paris, France, 14-18 July 2013. 

(2) EB welding of large components without a vacuum chamberChris Punshon and Allan Sanderson TWI Ltd, Cambridge, UKPaper presented at 7th International Conference on Beam Technology, Halle, Germany, 17-19 April 2007.

(3) Friction stir welding for the aerospace industry.Case Study  www.twi-global.com/news-events/case-studies/friction-stir-welding-for-the-aerospace-industry-207/ – 2014-05-06.