Metals hardness

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Where does inconel 718 rate compared to grade 8 carbon steel?  Also, what reference books do you guys really like in reference to modern alloys and metalurgy?  I have bought 3 different ones and they are either vague or antiques.Lots of toys.
Reply:Brandon,Your question is a little tough to answer for a couple reasons.  Assuming for a minute that when you say 'Grade 8 Carbon Steel', you're refering to the steel used to make Grade 8 fasteners.  These are typically made from a medium carbon steel, with a yield strength of about 150KSI.  Inconel has a room temp Yield strength of about 170KSI, when it's been properly heat treated.  There is a loose relationship between strength and hardness, although it's not always reliable for a great many reason that are too complicated to go into here.  Medium carbon steels can be quenched and tempered to produce a wide range of strengths and ductility.  The same can be said for Inconel 718.  The inconel alloy is designed to retain it's strength at high temperatures.  Medium carbon steels lose strength rapidly(by comparison) as you raise the temperature.  You could probably process a medium carbon steel(0.4-0.7 wt% Carbon) to have equal strength and hardness at room temperature as the inconel 718.Better answers can be provided if you give a bit more info on the situation that's prompting you to ask the question.So far as references go, I like Machinery's handbook, the Metals Handbook, and the ASM series of materials reference books.  Unfortunately, all are very expensive.  When I need them, I go to the library or sneak into a friends office where their company has them on hand.Last edited by A_DAB_will_do; 04-02-2008 at 04:52 PM.