Monel 400 Butt welding Nickel Alloy Pipe Fittings Anti Corrosion seamless elbow tee cross

1. Nickel based alloy Introduction

Nickel based alloys refer to a type of alloy that has high strength and certain resistance to oxidation and corrosion at high temperatures of 650-1000 ℃. According to their main properties, they are further subdivided into nickel based heat-resistant alloys, nickel based corrosion-resistant alloys, nickel based wear-resistant alloys, nickel based precision alloys, and nickel based shape memory alloys. High temperature alloys are divided into iron-based high-temperature alloys, nickel based high-temperature alloys, and cobalt based high-temperature alloys according to their different matrices. Nickel based high-temperature alloys are commonly referred to as nickel based alloys.

• Corrosion resistant alloy

The main alloying elements are copper, chromium, and molybdenum. It has good comprehensive performance and can withstand various acid corrosion and stress corrosion. The earliest application (produced in the United States in 1905) was nickel copper (Ni Cu) alloy, also known as Monel alloy (Ni 70 Cu30); In addition, there are nickel chromium (Ni Cr) alloys (which are nickel based heat-resistant alloys and corrosion-resistant alloys), nickel molybdenum (Ni Mo) alloys (mainly referring to Hastelloy B series), nickel chromium molybdenum (Ni Cr Mo) alloys (mainly referring to Hastelloy C series), and so on. Meanwhile, pure nickel is also a typical representative of nickel based corrosion-resistant alloys. These nickel based corrosion-resistant alloys are mainly used to manufacture components for various corrosion-resistant environments such as petroleum, chemical, and power.
Nickel based corrosion-resistant alloys often have an austenitic structure. In the state of solid solution and aging treatment, there are still intermetallic phases and metal carbonitrides present on the austenite matrix and grain boundaries of the alloy. Various corrosion-resistant alloys are classified according to their composition and characteristics as follows:
Ni Cu alloy has better corrosion resistance than nickel in reducing media, and better corrosion resistance than copper in oxidizing media. It is the best material for high-temperature resistance to fluorine gas, hydrogen fluoride, and hydrofluoric acid in the absence of oxygen and oxidants (see metal corrosion).
Ni Cr alloy, also known as nickel based heat-resistant alloy; Mainly used under oxidizing medium conditions. It is resistant to high-temperature oxidation and corrosion from gases such as sulfur and vanadium, and its corrosion resistance increases with the increase of chromium content. This type of alloy also has good resistance to hydroxide corrosion (such as NaOH, KOH) and stress corrosion.
Ni Mo alloys are mainly used under conditions of reducing medium corrosion. It is the best alloy that is resistant to hydrochloric acid corrosion, but its corrosion resistance significantly decreases in the presence of oxygen and oxidants.
Ni Cr Mo (W) alloy combines the properties of both Ni Cr alloy and Ni Mo alloy mentioned above. Mainly used under conditions of oxidation-reduction mixed media. This type of alloy has good corrosion resistance in high-temperature hydrogen fluoride, hydrochloric acid and hydrofluoric acid solutions containing oxygen and oxidants, and wet chlorine gas at room temperature.
Ni Cr Mo Cu alloy has the ability to resist both nitric acid and sulfuric acid corrosion, and also has good corrosion resistance in some oxidation-reduction mixed acids.

• Wear-resistant alloy

The main alloying elements are chromium, molybdenum, tungsten, and also contain small amounts of niobium, tantalum, and indium. In addition to its wear resistance, it also has good oxidation resistance, corrosion resistance, and welding performance. It can manufacture wear-resistant components and also serve as a coating material, which can be coated on the surface of other substrate materials through welding and spraying processes.
Nickel based composite powders include self fusing alloy powders and non self fusing alloy powders.
Non self fluxing nickel based powder refers to nickel based alloy powder that does not contain B, Si or has a low content of B and Si. This type of powder is widely used in plasma arc spraying coatings, flame spraying coatings, and plasma surface strengthening. Mainly including: Ni Cr alloy powder, Ni Cr Mo alloy powder, Ni Cr Fe alloy powder, Ni Cu alloy powder, Ni-P and Ni Cr P alloy powder, Ni Cr Mo Fe alloy powder, Ni Cr Mo Si high wear-resistant alloy powder, Ni Cr Fe Al alloy powder, Ni Cr Fe Al B-Si alloy powder, Ni Cr Si alloy powder, Ni Cr Si alloy powder, Ni Cr W based wear-resistant and corrosion-resistant alloy powder, etc.
Adding an appropriate amount of B and Si to nickel alloy powder forms nickel based self fluxing alloy powder. The so-called self fluxing alloy powder, also known as low melting alloy, is a series of powder materials formed by adding alloy elements (mainly boron and silicon) that can form low melting point eutectic crystals to nickel, cobalt, and iron-based alloys. The commonly used nickel based self fluxing alloy powders include Ni B Si alloy powder, Ni Cr B-Si alloy powder, Ni Cr B-Si Mo, Ni Cr B-Si Mo Cu, high molybdenum nickel based self fluxing alloy powder, high chromium molybdenum nickel based self fluxing alloy powder, Ni Cr W-C based self fluxing alloy powder, high copper self fluxing alloy powder, tungsten carbide dispersed nickel based self fluxing alloy powder, etc.
The role of various elements in alloys:
A: The effect of boron and silicon elements: significantly reduce the melting point of the alloy, expand the solid-liquid temperature range, and form low melting eutectic; Deoxygenation reduction and slagging function; Hardening and strengthening effects on coatings; Improve operational process performance
B: The role of copper element: improving corrosion resistance to non oxidizing acids
C: The role of chromium element: solid solution strengthening effect, passivation effect; Improve corrosion resistance and high-temperature oxidation resistance; Excess chromium is prone to form hard phases of chromium carbide and chromium boride with carbon and boron, thereby improving the hardness and wear resistance of the alloy
D: The role of molybdenum element: With a large atomic radius, solid solution causes significant lattice distortion, significantly strengthening the alloy matrix, improving the high-temperature strength and red hardness of the matrix; Can cut and reduce the network tissue in the coating; Improve resistance to cavitation and erosion.

• Precision alloy

Including nickel based soft magnetic alloys, nickel based precision resistance alloys, and nickel based electric heating alloys. The most commonly used soft magnetic alloy is a bimetallic alloy containing about 80% nickel, which has high maximum and initial magnetic permeability, low coercivity, and is an important iron core material in the electronic industry. The main alloying elements of nickel based precision resistance alloys are chromium, aluminum, and copper. These alloys have high electrical resistivity, low temperature coefficient of electrical resistivity, and good corrosion resistance, and are used to make resistors. Nickel based electric heating alloy is a nickel alloy containing 20% chromium, which has good oxidation and corrosion resistance and can be used for a long time at temperatures ranging from 1000 to 1100 ℃.

2. Monel 400 Seamless,welded Pipe Elbow

Monel 400 alloy (UNS N04400 or MCu-28-1.5-1.8 or Ni68Cu28Fe) is a nickel based alloy material with good corrosion resistance in seawater, chemical solvents, ammonia sulfur chlorine, hydrogen chloride, various acidic media such as sulfuric acid, hydrofluoric acid, hydrochloric acid, phosphoric acid, organic acids, alkaline media, salts, and molten salts.
Monel 400 alloy has excellent mechanical properties and is widely used at temperatures ranging from low to high, exhibiting excellent welding performance and medium to high strength.
Monel 400 is mainly used in fields such as chemistry, petrochemicals, and ocean development. It can be used to manufacture various heat exchange equipment, boiler feedwater heaters, petroleum and chemical pipelines, containers, towers, tanks, valves, pumps, reactors, shafts, etc.

Specification

Specifications : ASTM B366 / ASTM SB 366M

Dimensions : ANSI/ASME B16.9, B16.28, MSS-SP-43.

Size : NB ½" -24″ seamless, NB2"-72" welded in Sch 10s, 40s, 80s, 160s, XXS.

3. Application area
Nickel based alloys are used in many fields, such as:
1. Ocean: marine structures in the marine environment, desalination, aquaculture, and heat exchange of seawater.
2. Environmental protection field: flue gas desulfurization devices for thermal power generation, wastewater treatment, etc.
3. Energy sector: Atomic power generation, comprehensive utilization of coal, tidal power generation, etc.
4. Petrochemical industry: refining, chemical equipment, etc.
5. Food industry: salt production, soy sauce brewing, etc. Among the many fields mentioned above, ordinary stainless steel 304 is not competent. In these special fields, special stainless steel is indispensable and irreplaceable. In recent years, with the rapid development of the economy and the continuous improvement of the industrial level, more and more projects require higher grade stainless steel. With the increasing demand for nickel based alloys in various industries. In 2011, the market size of nickel based alloys in China reached 23.07 billion yuan, with a year-on-year growth rate of 19.47%. Therefore, the development level of the industry is steadily increasing.