2015年10月10日星期六

Methods to improve the quality and performance of the titanium sheet surface

A notable feature of titanium sheet is corrosion resistance, which is due to its affinity for oxygen is particularly large, can generate a dense oxide film on its surface, can protect the titanium against corrosion, in acidic, alkaline neutral salt solution and oxidizing medium has good stability, better than the existing stainless steel and other commonly used non-ferrous metal corrosion, even with platinum Bimei. Titanium is good or bad quality largely depends on the smelting process, including the chemical composition of titanium, titanium water cleanliness (gas, harmful elements, inclusions) and slab quality (segregation, decarbonization and surface condition) , these aspects is the critical control point smelting operations. In addition, industrial titanium also requires sufficient hardenability to ensure that the entire cross section of the spring to obtain uniform microstructure and mechanical properties. The main reason is that fatigue cracks of titanium oxide inclusions, and the class D inclusions on the fatigue life of the harm is greater than Class B inclusions. Therefore, foreign titanium plants and automobile plants in industrial titanium oxide inclusions put forward higher requirements, such as the Swedish SKF standard titanium oxygen content of less than 15 × 10-6, Class D inclusions below the Class B Inclusion thereof. Especially Al2O3 and TiN inclusions of titanium spring fatigue life damaging. For the production of high quality titanium industry, in the past usually an electric furnace - vacuum arc remelting ESR or other special smelting method.
Titanium is often used to make forging blank shape and dimensions close to the product, and then only for heat treatment and final machining. Casting temperature and the degree of deformation is a fundamental element of the resolution titanium arrangements function. Heat treatment of titanium blank with heat treatment of steel products factory is not the same, can not afford to arrange titanium resolution effect. Thus, the process of standard titanium products factory forging blank final important step has a unique effect. In order to make the rough titanium products factory forging together can achieve high strength and ductility, it is necessary that the entire amount of deformation of the blank is not less than 30%, deformation temperature does not exceed the phase transition temperature, and the temperature and the degree of deformation should strive throughout You can make the blank deformation spread evenly. Titanium products factory rough forging arrangements and functional uniformity of the stainless steel forgings. In metal strenuous activity area, after recrystallization heat treatment, its low times as vague crystal, fine grain high power axis is like; in difficult deformation zone, because of the small amount of deformation or no deformation, the arrangements often save the situation before the deformation. Thus forging some important blanks titanium products factory parts (such as compressor disks, blades, etc.), in addition to control of TB less distortion temperature outside and the appropriate degree of deformation, the rough handling of the original arrangement is very important, otherwise, coarse grain arrangement or some shortcomings will be inherited to the forging, heat treatment and after that they can not be eliminated, will lead to forging void.
Titanium surface reaction layer is the main factor affecting the physical properties of titanium, titanium rolling after annealing is completed required, which produces an oxide layer through the explosion of an alkali pickling method to remove the surface reaction layer of titanium.
1. Explosion base: What is critical base? Explosion alkali alkali solution that is in titanium products into boiling to the surface oxide layer reaction to the original titanium, thereby allowing subsequent pickling operation becomes possible. They use the product as a foam base, it is a white crystalline powder, soluble in water and dilute alkali solution; insoluble in alcohol and acid, alkaline aqueous solution.
2. Pickling: pickling quickly titanium surface reaction layer is completely removed, and no contamination of other surface elements. HF-HNO3 acid wash system is mainly used for titanium and titanium rods, titanium wire, titanium tube pickling, HF-HNO3 acid wash small quantity of hydrogen absorption lines can be controlled to reduce the concentration of HNO3 hydrogen storage, and the surface for bright treatment, the HF concentration is generally about 3% to 5%, the concentration of HNO3 is appropriate about 15% to 30%.



2015年10月5日星期一

TA15 Titanium Alloy Forgings

As one of the important selection of contemporary titanium aircraft structure design, and its level of application has even become an important indicator to measure the aircraft structure design selection advanced degree. Titanium for aircraft to reduce the overall weight of the structure, improve the structural design efficiency, improve structural reliability, improve the body's life, to meet the high temperature and corrosive environments and high load requirements, etc. can play a role unmatched by other metals. Titanium structure applied on an aircraft is now in the whole, large-scale direction. For titanium alloys, forging process is the most widely used method of molding to accurately alter the microstructure and properties of the alloy by deformation and heat treatment.
TA15 titanium alloy die forgings whole box is a large titanium aerospace structural parts with a typical representative, TNTI company through research TA15 Titanium thermal deformation characteristics combined with forging optimization of process parameters for large TA15 titanium alloy forgings forging production It provides basic data and processes of production experience.
For large-scale whole box TA15 titanium forging, through the study of the blank shape and size of the program to get the optimum blank. In the process of forging forging temperature, forging speed, impact deformation load of forging forming a comprehensive analysis, obtained for the whole box titanium forging reasonable parameters. By forming forging microstructure and mechanical properties of the test, the result was relevant standards for forging requirements.


2015年10月2日星期五

Tantalum wire can be used as surgical sutures

Tantalum can be made thinner than a human hair filaments used as surgical sutures, and other parts of the Achilles tendon rupture suture. Such sutures can even replace the tendon and nerve fibers.
Patella fracture and other parts
Statistics show that 33 cases with tantalum wire cerclage fixation for the treatment of various types of patellar fracture patients were followed up for 5 months to 16 years, except for two cases of mild traumatic arthritis, the remaining 31 cases have achieved good effect, no complications.
Advantages tantalum wire patella fractures that:
High tantalum wire strength, Rally, little elasticity, toughness, easy matter, knotted, stable fixation;
Tantalum wire excellent corrosion resistance and biocompatibility, nontoxic to humans, without surgery to remove again, it can carry a lifetime;
Simple tantalum wire cerclage fixation operation, less surgical trauma, time is short, and early postoperative knee joint to prevent joint stiffness and muscle atrophy;
The tantalum wire cerclage indications wide, not only for comminuted patella and good efficacy, but also applies to other parts of the fracture.

2015年10月1日星期四

Market sentiment promote the steady rise in nickel prices

Chairman Xi Jinping arrived in Seattle on September 22 visit to the US Open journey, heads the world's top two economies on September 25 formal meetings, the global financial and commodity markets are looking forward to Chinese investment to build the car in Massachusetts The first manufacturing base in the news, would not only indicates that "Made in China" opened a comprehensive "go out" of the big screen, and it will show the world is off the high-speed railway construction tide, meaning increment of stainless steel as well as nickel metal consumption demand very far-reaching.
Since 2015, nickel prices continued to rise in 2014 after endless downward trend shot up even more speculation in the short side no bottom line to wayward drop of nickel production has forced many companies have determined to cut or stop production, a lot of nickel ore trade Suppliers can no longer adhere to the business. A series of cold sad data has been a serious blow to the nickel industry chain Stable money ambition.
2015 nickel price a serious departure from the bottom line, triggering ferronickel and nickel electrolytic production trend continues to expand. Step by step because the price continued to decline and was finally dragged only to cut or stop production of nickel companies selected, even if the market stabilization signs of recovery, but also unable to resume production quickly organized to increase the effective supply of the market.