Inconel 686/UNS N06686/W.Nr.2.4606 bar, Pipe, Wire

Overview

INCONEL alloy 686 (UNS N06686/W.Nr. 2.4606) is a single-phase, austenitic Ni-Cr-Mo-W alloy offering outstanding corrosion-resistance in a range of severe environments. Its high nickel (Ni) and molybdenum(Mo) provide good resistance in reducing conditions,and high chromium (Cr) offers resistance to oxidizing media. Molybdenum (Mo) and tungsten (W) aid resistance to localized corrosion such as pitting. Iron(Fe) is closely controlled to enhance properties. Low carbon (C) helps minimize grain boundary precipitation to maintain corrosion-resistance in the heat-affected zones of welded joints. Resistance to general, pitting and crevice corrosion increases with the alloying(Cr+Mo+W) content, and INCONEL alloy 686 scores higher than competitive materials.

Limiting Chemical Composition, %

Nickel....................................................................................................................Balance

Chromium...........................................................................................................19.0-23.0

Molybdenum ......................................................................................................15.0-17.0

Tungsten.................................................................................................................3.0-4.4

Titanium...............................................................................................................0.02-0.25

Iron........................................................................................................................2.0 max.

Carbon................................................................................................................0.01 max.

Manganese .........................................................................................................0.75 max.

Sulfur ...................................................................................................................0.02 max.

Silicon .................................................................................................................0.08 max.

Phosphorus .........................................................................................................0.04 max.

Physical Constants

Mechanical properties-Room Tempreature

Corrosion Resistance

INCONEL alloy 686 offers outstanding resistance to general corrosion, to stress-corrosion cracking, and to pitting and crevice corrosion. Its resistance to intergranular precipitation during welding maintains its corrosion-resistance in the heat-affect zones of welded joints.It offers resistance to both reducing and oxidizing acids and to mixed acid solutions. It is especially suited to handling mixed acids containing high concentrations of halides. It has shown good resistance to mixed acid media with pH levels of 1or less, and chloride levels of over 100,000 ppm.Alloy resistance to pitting corrosion is often compared by reference to the so-called “Pitting Resistance Equivalency Number” - the PREN. Performance potential can be compared by the calculation:PREN = %Cr + 1.5 (%Mo + %W + %Nb)In ascending order of excellence, the highly alloyed INCONEL alloy 686 is proved as the optimum choice among commercially available, pit-resistant, Ni-Cr-Mo alloys.

Heat treatment

Solution treatment: This is the key step of heat treatment and is usually carried out at high temperatures from 1050°C to 1100°C. The purpose is to achieve solid solution of the alloy and improve its crystal structure. Through uniform heating and adequate insulation, solution treatment can improve the toughness and plasticity of the alloy, while reducing the residual stress and intergranular corrosion sensitivity.

Quenching treatment: After solution treatment, Inconel 686 is usually quenched. This step usually uses water quenching or oil quenching to cool the material quickly, thus making the crystal structure of the alloy denser and increasing its hardness and strength. Quenching treatment helps to enhance the wear and corrosion resistance of the alloy.

Aging treatment: After solution treatment and quenching treatment, Inconel 686 needs to be aged. Aging treatment is usually carried out in the temperature range of 750°C to 900°C, by controlling the time and temperature to further adjust the microstructure and properties of the alloy, thereby improving its strength and corrosion resistance.

In addition, it is worth noting that Inconel 686 alloys may require intermediate annealing during processing, either hot or cold working, to reduce work hardening and optimize the properties of the material. Solution treatment: This is the key step of heat treatment and is usually carried out at high temperatures from 1050°C to 1100°C. The purpose is to achieve solid solution of the alloy and improve its crystal structure. Through uniform heating and adequate insulation, solution treatment can improve the toughness and plasticity of the alloy, while reducing the residual stress and intergranular corrosion sensitivity.

Available Forms

We provide you with a variety of product forms, including but not limited to

● Bar & Rod

● Pipe &Tube

● Coil & Strip

● Plate & Sheet/Circle

● Wire & Welding

● Fitting (Flange, Bolts ,Elbow, Tee...)

● Customize