Inconel 718 plates has the following characteristics

 

●Easy processing

 

●High tensile strength, fatigue strength, creep strength and breaking strength at 700℃

 

●High oxidation resistance at 1000℃

 

●Stable chemical properties at low temperatures

 

●Good welding performance

 

Application field

 

Due to its high temperature strength at 700℃, excellent corrosion resistance and easy processing, it can be widely used in various high-demand occasions.

●Steam turbine

 

●Liquid fuel rocket

 

●Cryogenic Engineering

 

●acid environment

 

●Nuclear Engineering

 

Chemical composition

 

Similar grades

 

GH4169, GH169 (China), NC19FeNb (France), NiCr19Fe19Nb5, Mo3 (Germany), NA 51 (UK) Inconel718, UNS NO7718 (US) NiCr19Nb5Mo3 (ISO)

 

 

 

Physical propertiesedit

 

density

 

Density ρ=8.24g/cm3

 

Melting temperature range

 

Melting temperature range 1260～1320℃

 

Processing and heat treatment

 

Inconel718 alloy is a difficult-to-process material in the field of machining.

 

Warm up

 

The surface of the workpiece must be cleaned before and during heating to keep the surface clean. If the heating environment contains sulfur, phosphorus, lead or other low melting point metals, Inconel718 alloy will become brittle. Impurities come from marking paint, chalk, lubricating oil, water, fuel, etc. The sulfur content of fuel should be low. For example, the impurity content of liquefied gas and natural gas should be less than 0.1%, the sulfur content of city gas should be less than 0.25g/m3, and the sulfur content of petroleum gas should be less than 0.5%.

 

The heated electric furnace should have a more precise temperature control capability, and the furnace gas must be neutral or weakly alkaline, and fluctuations in the oxidizing and reducing properties of the furnace gas should be avoided.

 

Thermal processing

 

The suitable hot working temperature of Inconel718 alloy is 1120-900℃. The cooling method can be water quenching or other rapid cooling methods. After hot working, it should be annealed in time to ensure the best performance. The material should be heated to the upper limit of the processing temperature during hot processing. In order to ensure plasticity during processing, the final processing temperature when the deformation reaches 20% should not be lower than 960°C.

 

Cold working

 

Cold working should be carried out after solution treatment. The work hardening rate of Inconel718 is greater than that of austenitic stainless steel, so the processing equipment should be adjusted accordingly, and there should be an intermediate annealing process during the cold working process.

 

Heat treatment

 

Different solution treatment and aging treatment processes will result in different material properties. Due to the low diffusion rate of γ" phase, Inconel718 alloy can obtain the best mechanical properties through long-term aging treatment.

 

Polished

 

The oxide near the weld of the Inconel718 workpiece is more difficult to remove than the stainless steel. It needs to be polished with a fine sanding belt. Before pickling in a mixed acid of nitric acid and hydrofluoric acid, the oxide should be removed with sandpaper or a salt bath deal with.