Titanium and its alloys
Titanium and its alloy have low density (4.51g/cm3), high strength (some reach 1000MPa), high specific strength, and high and low temperature performance (-250℃ ~ 500℃) and anti-fatigue performance (fatigue limit is twice of steel) excellent, so it is very suitable for aircraft, missiles, rockets and other high-speed aircraft use. The application of titanium alloy fastener produces the effect of weight reduction, to improve the aircraft and spacecraft propulsion force, increase the range, fuel saving, reduce the cost of launch will have a huge effect. In modern aircraft manufacturing, a single aircraft uses hundreds of thousands to millions of fasteners. Titanium alloy fasteners account for up to 90% of threaded fasteners. Titanium alloy fastener has become the most important "aerospace fastener" variety.
Titanium alloy fastener has excellent corrosion resistance, especially its positive potential property is just matched with carbon fiber composite material, which can effectively prevent the galvanic corrosion of fastener. Therefore, not only titanium structure, aluminum structure, and even some composite materials can also use titanium alloy fasteners. This property cannot be replaced by any other material, which is also the rapid development of titanium fasteners.
Titanium Tube Supplier says Because titanium's corrosion resistance to seawater is better than all metals, it has special stability in static or high-speed flowing seawater. In addition, the fasteners made of titanium alloy are ideal for submarine, warship, civilian vessel and desalination plant applications.
Heavy corrosive environment in industrial areas
In the petroleum, chemical, metallurgy, electric power and other industries related facilities, equipment, fasteners and connectors not only to bear a certain load, but also by a variety of acid, alkali medium strong corrosion, working conditions are very harsh, the use of titanium alloy fasteners is the best choice. Because, titanium in high temperature wet chlorine environment has strong corrosion resistance. For example, titanium in room temperature chlorine water, corrosion rate is 0.000565mm/a; In chlorine water at 80℃, the corrosion rate is 0.00431mm/a. In 95% wet chlorine water, the corrosion rate is 0.00096mm/a. Therefore, titanium alloy fasteners are the best substitute for stainless steel fasteners.
Medical and pharmaceutical production field
Titanium fasteners are increasingly used in pharmaceutical equipment, medical instruments, surgical instruments and artificial bones because titanium is resistant to internal fluid corrosion, non-magnetic, and has good biocompatibility and is harmless to human body.
High-end sports equipment field
Titanium alloy fasteners have considerable application prospects in the manufacture of high-grade sports equipment (such as golf clubs), high-grade bicycles and high-grade cars. In 2010, the titanium used in cars and motorcycles alone reached nearly 8000t. As the automobile industry is the largest user of fastener products, its demand accounts for about 18%-20% of the total fastener sales. Therefore, it is of great significance to further expand the market space of automotive titanium alloy fasteners.
Generally, the tensile strength of titanium alloy fasteners is 1000 ~ 1500MPa, which is equivalent to the strength level of 30CrMnSiA steel after quenching and quenching. The shear strength of titanium alloy fasteners is the same as that of alloy steel, but the density is only 58% of steel. Therefore, in foreign advanced aircraft, 30CrMnSiA steel fasteners have been basically replaced by titanium alloy fasteners. Due to the high specific strength (can reach the specific strength of high strength aluminum alloy), the temperature resistance of 350℃. A variety of titanium alloy fasteners for modern aircraft materials, mainly ordinary titanium bolts, interference bolts, special bolts and so on.
Common titanium fasteners mainly include: common titanium bolt, high lock bolt, Addie bolt system, etc.
Ordinary titanium bolts: according to the head type, they are divided into countersunk head (100°, 130°) bolts, hexagon bolts, twelve Angle bolts, twelve Angle flange bolts, etc. 100° countersunk head bolts have a variety of grooves, such as Phillips cross grooves, high torque cross grooves, three wing grooves, high torsion slot and so on. Having a clearance or interference diameter.
High lock bolt: It is a threaded fastener that can be mounted on one side. It is one of the most widely used fasteners in aircraft. According to the force can be divided into tensile type, shear type. Bolts with 100° countersunk head and flat convex head, aluminum high lock nuts for shear type, stainless steel nuts for tensile type. The rod diameter is divided into clearance type, interference type and short thread interference type. Nuts are divided into ordinary high-lock nuts, sealed high-lock nuts (with nylon washers) and self-aligned high-lock nuts according to their uses.
The technical requirements of aerospace titanium alloy fasteners are almost strict. In addition to the requirements of high specific strength, high temperature resistance, low temperature resistance, corrosion resistance, the pursuit of as high as possible fatigue life, but also the requirements of anti-loose, self-locking, shape memory and other functions. The advanced nature, reliability and rationality of installation and connection should achieve a very ideal situation. That is, after the assembly process is completed, the clamping force, self-locking force and interference quantity should be guaranteed reliably. The thread of titanium alloy fasteners is mostly large arc bottom, precision and high MJ thread (metric) or UNJ thread (inch), its technical content is much higher than that of ordinary fasteners
Heavy corrosive environment in industrial areas
In the petroleum, chemical, metallurgy, electric power and other industries related facilities, equipment, fasteners and connectors not only to bear a certain load, but also by a variety of acid, alkali medium strong corrosion, working conditions are very harsh, the use of titanium alloy fasteners is the best choice. Because, titanium in high temperature wet chlorine environment has strong corrosion resistance. For example, titanium in room temperature chlorine water, corrosion rate is 0.000565mm/a; In chlorine water at 80℃, the corrosion rate is 0.00431mm/a. In 95% wet chlorine water, the corrosion rate is 0.00096mm/a. Therefore, titanium alloy fasteners are the best substitute for stainless steel fasteners.
Medical and pharmaceutical production field
Titanium fasteners are increasingly used in pharmaceutical equipment, medical instruments, surgical instruments and artificial bones because titanium is resistant to internal fluid corrosion, non-magnetic, and has good biocompatibility and is harmless to human body.
High-end sports equipment field
Titanium alloy fasteners have considerable application prospects in the manufacture of high-grade sports equipment (such as golf clubs), high-grade bicycles and high-grade cars. In 2010, the titanium used in cars and motorcycles alone reached nearly 8000t. As the automobile industry is the largest user of fastener products, its demand accounts for about 18%-20% of the total fastener sales. Therefore, it is of great significance to further expand the market space of automotive titanium alloy fasteners.
Generally, the tensile strength of titanium alloy fasteners is 1000 ~ 1500MPa, which is equivalent to the strength level of 30CrMnSiA steel after quenching and quenching. The shear strength of titanium alloy fasteners is the same as that of alloy steel, but the density is only 58% of steel. Therefore, in foreign advanced aircraft, 30CrMnSiA steel fasteners have been basically replaced by titanium alloy fasteners. Due to the high specific strength (can reach the specific strength of high strength aluminum alloy), the temperature resistance of 350℃. A variety of titanium alloy fasteners for modern aircraft materials, mainly ordinary titanium bolts, interference bolts, special bolts and so on.
Common titanium fasteners mainly include: common titanium bolt, high lock bolt, Addie bolt system, etc.
Ordinary titanium bolts: according to the head type, they are divided into countersunk head (100°, 130°) bolts, hexagon bolts, twelve Angle bolts, twelve Angle flange bolts, etc. 100° countersunk head bolts have a variety of grooves, such as Phillips cross grooves, high torque cross grooves, three wing grooves, high torsion slot and so on. Having a clearance or interference diameter.
High lock bolt: It is a threaded fastener that can be mounted on one side. It is one of the most widely used fasteners in aircraft. According to the force can be divided into tensile type, shear type. Bolts with 100° countersunk head and flat convex head, aluminum high lock nuts for shear type, stainless steel nuts for tensile type. The rod diameter is divided into clearance type, interference type and short thread interference type. Nuts are divided into ordinary high-lock nuts, sealed high-lock nuts (with nylon washers) and self-aligned high-lock nuts according to their uses.
The technical requirements of aerospace titanium alloy fasteners are almost strict. In addition to the requirements of high specific strength, high temperature resistance, low temperature resistance, corrosion resistance, the pursuit of as high as possible fatigue life, but also the requirements of anti-loose, self-locking, shape memory and other functions. The advanced nature, reliability and rationality of installation and connection should achieve a very ideal situation. That is, after the assembly process is completed, the clamping force, self-locking force and interference quantity should be guaranteed reliably. The thread of titanium alloy fasteners is mostly large arc bottom, precision and high MJ thread (metric) or UNJ thread (inch), its technical content is much higher than that of ordinary fasteners