The lower critical temperature value for steel is given in which unit in this material?

The lower critical temperature value for steel is given in which unit in this material?

• A. Fahrenheit
• B. Celsius
• C. Kelvin
• D. Rankine

Answer: (A)

Critical temperatures for steel in this material are presented in Fahrenheit. This scale is commonly used in welding and industrial practice in the US, so the lower critical temperature (Ac1) is shown in °F (for reference, Ac1 is about 1341°F, which is roughly 727°C). Using Fahrenheit here keeps the data consistent with the rest of the material and avoids conversions you’d have to do if Celsius or Kelvin were used. Rankine isn’t the unit shown in this context.

Critical temperatures for steel in this material are presented in Fahrenheit. This scale is commonly used in welding and industrial practice in the US, so the lower critical temperature (Ac1) is shown in °F (for reference, Ac1 is about 1341°F, which is roughly 727°C). Using Fahrenheit here keeps the data consistent with the rest of the material and avoids conversions you’d have to do if Celsius or Kelvin were used. Rankine isn’t the unit shown in this context.