ASTM B265 Grade 2 Titanium Strips & Coils

Definition, Characteristics & Applications

ASTM B265 cold-rolled grade 2 titanium strips, packaged in coil.

According to ASTM B265, any product made of Grade 2 unalloyed titanium, 4.75 mm and under in thickness and less than 610 mm in width is classified as Grade 2 titanium strip. Since titanium strips are often furnished in coils, they are also called titanium coils in that case. Grade 2 unalloyed titanium is a typical commercially pure titanium, which is the “workhorse” for industrial applications. Due to its excellent corrosion resistance and high specific strength, ASTM B265 grade 2 titanium strips are mainly used for the manufacture of welded titanium tubes, which are further extensively used for heat exchangers, condensers, coolers and evaporators in coastal power plants, seawater desalination systems, offshore drilling platforms, and petroleum refineries. Grade 2 titanium strips can be used in continuous service up to 425°C [800°F] and in intermittent service up to 540°C [1000°F].

Chemical Composition Requirements

Mechanical Properties

ASTM B265 grade 2 titanium strips supplied in flat piece.

Manufacture & Heat Treatment

ASTM B265 grade 2 titanium strips are generally supplied in cold-worked and heat treated conditions. The base material for the production is titanium sponge, which is attained by the reduction of titanium tetrachloride with magnesium under an inert gas atmosphere. The titanium sponges are compacted into an long electrode, which is subsequently fed into the vacuum arc remelting furnace to produce titanium ingots. The titanium ingot will be further processed (usually forged) to get the required titanium slab for the next rolling process.

The tandem hot-rolling mill for the blooming process of titanium slabs.

The titanium slab shall be first hot rolled on a tandem hot-rolling mill or a steckel mill at elevated temperatures. After multiple passes of hot rolling operations, titanium coils in thickness of 2.8~3.5 mm can be attained. The hot-rolled titanium coil will be annealed, and cleaned by the subsequent sandblasting and pickling processes to remove the surface oxide layer. The finished coil is then fed to the cold rolling mill. Through multi-pass cold rolling operations, much thinner titanium coils in thickness 0.03~1.50 mm can be attained. After the final heat treatment, the cold rolled titanium coils can be either horizontally or vertically sheared to produce flat strips or split coils, respectively.

The multi-pass cold rolling mill for the production of titanium coils.

The final heat treatment of ASTM B265 grade 2 titanium strips or coils shall be annealing in continuous-inert-gas or vacuum atmosphere. The main purpose of annealing is to make the titanium strips completely recrystallized to attain uniform grain size and mechanical properties. The titanium grade 2 strips or coils are degreased and cleaned before annealing. They shall be heated in the protective or vacuum atmosphere to a temperature between 650°C and 700°C, holding for 2.5~4.5 hours, and then cooled in the same furnace condition gradually.

Dimensional & Weight Tolerances

The permissible variations in weight of titanium strip is (+10%, -0). For permissible variations in thickness of titanium strip, please contact us at info@pipingpipeline.com