Fixations en alliage de zirconium

Zirconium Alloy Zr702/ UNS:R60702

Alloy Zr702 is a zirconium grade characterized by immunity to stress corrosion cracking and high resistance to pitting and crevice corrosion. The grade has very good corrosion resistance in most organic acids, excellent corrosion resistance in mineral acids, good corrosion resistance in strong alkalis and moderate mechanical strength.

Zr702 is used in environments where even the best stainless steels are not sufficiently corrosion resistant.

Zr702 zirconium is used in chemical plants in valves, pipes, heat exchangers and pumps. These systems are, for example, apparatus for the production of acetic acid, hydrochloric acid or urea. Even in the medical field Zr702 is used because it is biocompatible and shows no toxic effects. Another important application of zirconium 702 is the nuclear technology.

Chemical Analysis:

Zr+Hf	Hf	Fe+Cr	H	N	C	O
Min	Max	Max	Max	Max	Max	Min
99.2	4.5	0.2	0.005	0.025	0.05	0.16

Mechanical Properties Tensile Inspection:

Yield Strength		Tensile Strength		Elongation
Rp0.2		Rm
MPa	ksi	MPa	ksi	A2"
min	min	min	min	%
205	30	380	55	16

Physical Properties:

Density	Melting point	Thermal conductivity	Elastic bending modulus	Thermal expansion
6.5g/cm3	1852°C	22 W/(m °C)	99.3 GPa	5.4x10-6 /°C

Use:

1. Industrial use:

① Getter: Zirconium can strongly absorb nitrogen, hydrogen, oxygen and other gases. This property of zirconium has been widely used in the electric vacuum industry.

② Metallurgy: Zirconium has a strong deoxidation, nitrogen, sulfur, so it can be used as the metallurgical industry of the "vitamin".

③ Zirconium alloy: Zirconium alloy is a non-ferrous alloy composed of zirconium and other elements. Zirconium can be alloyed with tin, niobium, iron, etc. Zirconium alloy in 300 ~ 400℃ high temperature and pressure water and steam has good corrosion resistance, moderate mechanical properties, low atomic thermal neutron absorption cross section, has good compatibility to nuclear fuel, and is often used as the core structure material of water cooled nuclear reactor. In addition, zirconium has excellent corrosion resistance to a variety of acids, bases and salts, and has a strong affinity with gases such as oxygen and nitrogen. Therefore, zirconium alloy is also used in the manufacture of corrosion resistant components and pharmaceutical machinery components, and is widely used as a non-evapotranspiration type sterilizer in the electric vacuum and light bulb industries.

Zirconium alloys include zirconium - tin series and zirconium - niobium series. The former alloy grade Zr-2, Zr-4, the typical representative of the latter is Zr-2.5Nb. Zirconium alloy has good plasticity, which can be made into pipe, plate, bar and wire by plastic processing. Its weldability is good, can be used for welding processing.

Atomic energy industry: can be used as reactor core structural materials. Zirconium is used almost exclusively as a cladding for uranium fuel components in nuclear reactors, as well as in the manufacture of flash lamps for photography, and in corrosion-resistant vessels and pipes, particularly in hydrochloric and sulfuric acid.

2. Military use:
① Military: armored steel containing zirconium, cannon forging steel, stainless steel and heat-resistant steel are important materials for the manufacture of armored vehicles, tanks, cannons and bulletproof plates and other weapons.
(2) Atomic energy and nuclear energy: zirconium has outstanding nuclear energy, is an indispensable material for the development of atomic energy industry, China's large nuclear power plants generally use zirconium material.

Zirconium has amazing corrosion resistance, extremely high melting point, ultra-high hardness and strength, and is widely used in aerospace, military, nuclear reaction, atomic energy fields. As an aerospace material, zirconium is superior to titanium in all aspects.