What is the difference between nickel-based alloys 800, 800H and 800HT?

The chemical composition of INCOLOY 800/800H/800HT is very similar, so they all have good resistance to corrosion by reduction, oxidation and nitriding media as well as resistance to corrosion by alternating redox media, and have high metallurgical stability in high temperature long-term applications. However, due to the different (Al + Ti) content of the three, resulting in the application of the three materials in different environments, as shown in.

800 has various properties at sub-zero, room temperature and 600℃ high temperature.

800H has good tensile strength above 600°C due to the (Al+Ti) content not higher than 0.7%, and still has good toughness when working for a long time below 700°C. 800HT has good tensile strength above 700°C and has good toughness when working for a long time below 700°C.

800HT has excellent yield strength at 700℃ and above. It is recommended to select materials according to the environment in which they are often used.

Application areas: heat exchangers, electric heat pipes, heat treatment parts, acetic acid gypsum production and nuclear industry, etc.

Incoloy 800, incoloy 800H (UNS N08810) and incoloy 800HT (UNS N08811) are all nickel alloys with different chemical compositions.

Chemical composition of Incoloy 800H:

Alloy % Nickel Chromium Iron Carbon Manganese Silicon Copper Sulfur Aluminum Titanium

800 min 30 19 0.15 0.15

Max. 35 23 Balance 0.10 1.5 1 0.75 0.015 0.60 0.60

800H min 30 19 0.05 0.15 0.15

Max. 35 23 Balance 0.10 1.5 1 0.75 0.015 0.60 0.60

800HT min. 30 19 0.06 0.15 0.15

Max 35 23 Balance 0.10 1.5 1 0.75 0.015 0.60 0.60

0.85-1.20 for aluminum + titanium

incoloy800H (UNS N08810) alloy alternative incoloy800 should be possible, 800HT is mainly for aluminum and titanium content requirements. Specific physical properties, high temperature corrosion resistance.