Inconel686 (N06686) solid solution strengthened corrosion-resistant nickel-based alloy
Inconel 686/N06686 is a NI-Cr-Mo solid solution strengthened corrosion-resistant nickel-based alloy. It has outstanding corrosion resistance in harsh corrosive environments. It is mainly used in chemical processing, pollution control, papermaking, industrial and municipal waste disposal, etc. Heat exchangers, reaction vessels, delivery pipes, etc.
According to Huntington Specialty Materials of the United States, Inconel 686 alloy, which has excellent corrosion resistance, has replaced the K-500 alloy used on U.S. Navy ships as connectors. Alloy 686 is a solid solution strengthened alloy that achieves high strength through cold working. In particular, the cold-worked 686 alloy shows outstanding hydrogen embrittlement resistance and corrosion resistance, such as excellent strength, ductility and toughness. The 1.3×33cm (0.5×13 inches) bolts are made of 38Inm (15 inches) cold-worked 686 alloy rods with a standard R1Tr ultimate tensile strength of 993MPa. These processed bolts have processed connectors and wedges. The middle part of the tension test showed good performance.
Inconel686(UNS N06686/W.Nr. 2.4606)
chemical composition(%)
Ni Yu
Cr19.0-23.0
F≤2.0
Mo15.0-17.0
Ti0.02-0.25
W3.0-4.4
C≤0.01
Mn≤0.75
S≤0.02
Si≤0.08
P≤0.04
Physical properties (room temperature):
Density (g/cm3) 8.73
Melting point (℃) 1338-1380
Specific heat (J/kg-℃) 373
Resistivity (ohm circ mil/ft) 744.4
Uniform corrosion of inconel products can occur in acidic or hot alkaline solutions. Through this mechanism the losses can be estimated and allowed in the planning. The corrosion rate of inconel products is very slow when the metal is in a passive state and generally resists corrosion better with larger chromium content, but other solutes can be harmful.
The chemical composition near the grain boundaries of inconel steel products can be altered by the precipitationof chromium-rich particles. The resulting chromium-poor zone at the grain boundaries makes 4cr13 stainless steel pipe products susceptible to intergranular anodic attack, even under stress-free conditions.
Specifying an inconel steel product means a Cr content of just over 12%. Most stainless steels are based on the Fe-Cr-C and Fe-Cr-Ni-C systems, but other alloying elements are also important.
Inconel steel products can exist in several crystallographic modes, the most common of which are body-centered cubic (bcc) and face-centered cubic (fcc). In pure iron, the fcc structure remains at a melting temperature between 910 and 1400°C, which is the moment distance below and above the body-centered cubic structure (as high as 1539°C).
The importance of the metallurgical transformation of inconel steel products at this stage cannot be overestimated. This transformation allows a wide range of microstructures to be achieved through controlled heat treatment. Essentially related to microstructure, mechanical function, and thus, inconel steel products are able to obtain strength, toughness, etc. within a very large scale. Conventional production of inconel steel 100 MPa exceeds 1 GPA and has strong competitive strength. Therefore, the first thing to pay attention to is the knowledge of the relative stability of the bcc and fcc structures of iron inconel steel.
Features: Excellent corrosion resistance, can be used as a universal weld filler metal.
Alloy 686 was specifically developed to find an alloy that would exhibit excellent corrosion resistance in many harsh corrosive environments.
686 alloy is used in the harshest working environments, mainly in chemical processing, pollution prevention, pulp and paper making, industrial waste and domestic waste treatment. Chemical processing includes heat exchangers, reactors, evaporators and transfer pipelines. In terms of air pollution prevention and control, there are chimney fabrics, pipes, furnace doors, scrubbers, flue gas reheaters, propellers, and outer covers.
Product options available
Pipes, sheets, thick plates, strips, round bars, hexagonal bars, wires, forgings
Main enforceable standards
UNS N06686
ASTM B163, B462, B564, B574, B575, B619, B622, B626, B751, B775, B829, B906, F467, F467M, F468, F468M
ASME SB-163, SB-462, SB-564, SB-574, SB-575, SB-619, SB-622, SB-626, SB-751, SB-775, SB-829, SB-906
ASME Code Case 2198
SAE/AMS J2295, J2271, J2655, J2280, J2485
DIN 17744, 17750, 17751, 17752, 17753, 17754
Werkstoff Nr.2.4606
VdTüV 515
NACE MR-0175/ISO 15156
