Abstract: The present disclosure relates generally to building surface panels, for example, suitable for covering a support structure of a building. The present disclosure relates more particularly to a building surface panel including a hollow panel body, a fastening strip attached to the panel body, and an overhang attached to the panel body and extending along the lower side of the building surface panel. The building surface panel includes a rear-facing engagement surface disposed at the upper side of the building surface panel and a front-facing engagement surface disposed at the lower side of the building surface panel. The front facing engagement surface is configured to engage a rear facing engagement surface of a lower neighboring building surface panel.

Abstract: A method for extruding metals and alloys, particularly difficult-to-work high temperature alloys, is described which comprises inserting a billet of the metal or alloy into an extrusion can, heating the canned billet to a temperature in a temperature range in which the ductility of the billet material is substantially maximum, cooling the canned billet sufficiently to establish a preselected temperature difference between the billet and can at which the difference between the flow stress of the billet material and the flow stress of the can material is substantially minimum, and extruding the canned billet to preselected shape.