High strength and toughness light zirconium alloy can be divided into crystalline zirconium alloy and amorphous zirconium alloy.
Crystalline zirconium alloy can be divided into α type zirconium alloy, α+β type zirconium alloy and β type zirconium alloy according to its phase composition. From the perspective of mechanical properties, α-type zirconium alloy has higher strength (tensile strength up to 1600MPa) and hardness, and its friction and wear resistance is better than that of titanium alloy. After surface treatment, its wear resistance is improved obviously. There are two phases with different crystal structures in α+β type zirconium alloy, which have excellent comprehensive mechanical properties. The β-type zirconium alloy has more slip systems and higher plasticity (up to 30% elongation after fracture).
Amorphous zirconium alloy is a typical metastable state in which the atoms of solid matter are arranged in a near-range order and a long-range disorder. Therefore, the amorphous material is also called metal glass or liquid metal. The hardness of zirconium based amorphous alloy is above 60HRC (more than 20% higher than stainless steel), with ultra-high strength, wear resistance, far beyond alloy steel (for example: specific strength is 2.4 times of 20CrMnTi alloy steel), and the density is lower than alloy steel by more than 30%, without surface treatment that has a smooth surface, but has the limit of critical size.
In addition to all the advantages and characteristics of zirconium alloy, both crystalline zirconium alloy and amorphous zirconium alloy have their own advantages. The classification of zirconium alloy provides simple and clear guidance for the application of zirconium alloy and material selection of products.
Zirconium has the characteristics of non-toxic, non-magnetic, human affinity, low elastic modulus and stable properties. Traditional stainless steel (including toxic elements such as nickel chrome), nickel alloy (more than 20% of people will produce caused by nickel allergy) or titanium elastic modulus is larger, can cause the stress shielding effect after implantation in the human body, cause the symptom such as human body muscle atrophy, and zirconium alloy is not only a biological compatibility, and lower elastic modulus, as oral repair material, bone implant materials, Orthopedic repair materials and surgical instruments have been widely used. The Zr-Nb alloy used in the nuclear industry has been implanted into the human body as a replacement bone, without debris spalling, with low osteolysis (CoCr alloy has a higher risk of osteolysis than CoCr alloy, which is also used as bone implant material), and its service life is several times longer than that of the traditional implant material. Zirconium alloy is widely used in oral medical treatment. Zirconium alloy is widely used in orthodontic appliance and oral implant. And in neurosurgery, which is an extremely sensitive field of medicine, zirconium wires can be used as a suture material for brain surgery.
