Effect of Annealing Temperature on Microstructure and Properties of Cold Rolled Titanium Plate
Industrial pure titanium has excellent corrosion resistance, good mechanical properties and welding performance, can be used as an important corrosion resistant structural materials, widely used in chemical equipment, coastal power generation equipment, desalination plant and ship parts, etc., is China's strong development of titanium One of the materials. Cold rolling can be obtained with good surface quality, thickness tolerance of pure titanium plate strip, but because the industrial pure titanium is a less sliding system, the symmetry of poorly packed hexagonal metal, titanium after cold deformation, its Lattice distortion, the internal lattice to produce a large number of defects and dislocations, so that the internal energy of titanium, titanium in a metastable state. Through the annealing treatment, can eliminate the internal stress of a cold-rolled titanium plate, get no distortion of brain structure, improve the performance of titanium plate. At present, the reported reports mainly focus on the effect of annealing process on the microstructure and properties of titanium or titanium alloy. However, in the actual production process, the same annealing process is used to treat different specifications cold rolled titanium plate. or even part cannot meet the user requirements. Therefore, the researchers of different specifications of the cold rolled titanium plate annealing, comparative study of different annealing temperature of cold rolled titanium plate microstructure and properties. The experimental material is 3.5mm hot-rolled titanium plate rolled by the multi-pass cold rolled thickness of 0.5mm and 1.0mm specifications of TA1 pure titanium cold-rolled coil, the coil cut the sample processed into a number of mechanical tensile standard The Before the heat treatment, the sample was in the cold and hard state, no yield, elongation after breaking only 6%, the organization for the processing of streamlined fibrous tissue, but for 1.0mm cold-rolled titanium plate, fibrous tissue showed a certain direction, Visible grain boundary, this is because 1.0mm titanium plate deformation is not 0.5mm cold-rolled titanium plate, the original grain structure in the cold rolling process is not fully broken. The furnace was heated by the box-type resistance furnace, and the furnace was cooled to 100 ° C or lower after heating for 1 h with the furnace temperature to the set temperature (550, 570, 590, 610, 630, 650, 670, 690, 710 ° C)
After the baked cool. After annealing, the mechanical properties of the samples were studied, and the samples were corroded and the grain size was graded. The results show that: (1) 0.5mm cold-rolled titanium plate heat preservation after 1h, 570 below the recrystallization occurred, 670 when the grain has been basically equalization, to 690 above the brain grows rapidly. And from 1.0mm cold rolled titanium plate under this condition, no significant uncrystallized grains were observed, but at 610 ~ 650 grain fines, uniform distribution. (2) with the increase of annealing temperature, the yield strength and tensile strength of 0.5 and 0.1mm cold rolled titanium plate samples decreased gradually, and the rate of decrease of yield strength was faster than that of tensile strength. In the experimental temperature range elongation change is not clear, but the cold hard state elongation increase is very large. (3) comprehensive organization and performance, 0.5mm, 1.0mm cold rolled titanium plate suitable annealing temperature should be controlled at 630 ~ 670, 610 ~ 650.
