Bennett Posted July 10, 2007 Share Posted July 10, 2007 (edited) Co Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
Bennett Posted July 11, 2007 Author Share Posted July 11, 2007 (edited) To m." Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
Greg Thomas Obach Posted July 12, 2007 Share Posted July 12, 2007 hey... real interesting read... i had to scramble to find a periodic table to check this one out... .. and i thought niobium was weird... it'll be cool to see if it can be made into a blade G North Shore Forge & Ironworks Link to comment Share on other sites More sharing options...
Bennett Posted July 12, 2007 Author Share Posted July 12, 2007 (edited) He Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
Bennett Posted July 12, 2007 Author Share Posted July 12, 2007 (edited) A Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
kb0fhp Posted July 13, 2007 Share Posted July 13, 2007 (edited) A few more properties of new, little friend, iridium...... " Rhenium's melting point of 3180º C is second only to tungsten. Only osmium, iridium, and platinum exceed its density of 21.04 g/cc. Because of its high melting point, rhenium is a refractory metal. In that classification, rhenium is unique. It is the only refractory metal that does not form carbides. Its crystal structure is hexagonal close-packed (hcp), while other refractory metals have a body centered cubic (bcc) structure. Rhenium also does not have a ductile-to-brittle transition temperature it maintains its ductility from absolute zero all the way to its melting point and also has a high modulus of elasticity. This means that structures made of rhenium will have very good stability and rigidity. A high re-crystallization temperature is a pre-requisite for good creep resistance and among refractory metals, rhenium is the highest. At temperatures up to 2800º C and high stresses, the rupture life of rhenium is longer than tungsten. The metal also accommodates wide swings in temperature - large thermal expansions and contractions - without incurring mechanical damage." Sound good? This is pretty interesting stuff. Initially, looking at the periodic table, I would expect it to act like Mn, but because the crystal structure is different - and the size of the lattice is different, it would probably be a dispersoid former, and act to raise the recrystallization temperature. It might also report to the grain boundaries, and act to pin the grain boundaries, preventing or minimizing grain growth. It could also act to slow creep. But regardless, it would not be soluble in Fe to any great amount because of the large mis-match in the crystal lattice. But then, it could also be fairly soluble like cobalt which is also hexagonal - it depends on the matching between the a and c values of the unit cell - I am not sure how much bigger the unit cell of Re is compared to cobalt. I have tried to look for a Re-Fe phase diagram with no luck. I would suspect that it would be similar to a Co-Fe phase diagram, but with a smaller solid solubility. I imagine that it would make some interesting intermetallics that may form at the grain boundarys - and become brittle because of the intermetallics, and result in intergranular fracture (the rock candy fracture)....I really don't know. OK - I found a really small portion of a phase diagram - valid from 0-45at% of Re....looks like it is soluble in austenite up to about 5% at about 500C, then forms an intermetallic. I would then suspect that it would report to the grain boundaries, and become a brittling agent.... Scott Edited July 13, 2007 by kb0fhp D. Scott MacKenzie, PhD Heat Treating (Aluminum and Steel) Quenching (Water, Polymer, Oil, Salt and Mar-Tempering) Link to comment Share on other sites More sharing options...
Bennett Posted July 13, 2007 Author Share Posted July 13, 2007 (edited) Ve Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
kb0fhp Posted July 14, 2007 Share Posted July 14, 2007 I tried to get a bigger diagram - but that was free - a bigger diagram cost big bucks for subscription D. Scott MacKenzie, PhD Heat Treating (Aluminum and Steel) Quenching (Water, Polymer, Oil, Salt and Mar-Tempering) Link to comment Share on other sites More sharing options...
Bennett Posted July 14, 2007 Author Share Posted July 14, 2007 (edited) [q Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
Bennett Posted July 26, 2007 Author Share Posted July 26, 2007 (edited) W Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
Bennett Posted September 23, 2007 Author Share Posted September 23, 2007 (edited) Thi Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
kb0fhp Posted September 23, 2007 Share Posted September 23, 2007 OK - an element is an element - but remember elements have an electron shell filled with varing numbers of electrons based on their position on the periodic table. They also have a nucleus which is filled with neutrons and protons (from http://www.aboutnuclear.org/view.cgi?fC=Th...e_of_the_Atom): Even though the number of protons in the nucleus is the same for all atoms of a particular element, the number of neutrons in the nucleus can differ for different atoms of the same element. Atoms of an element that contain the same number of protons, but different numbers of neutrons, are called isotopes of the element. Isotopes are identified by adding the number of protons and neutrons together -- a number which is referred to as the mass number. For example, hydrogen: the element hydrogen has 3 isotopes: hydrogen 1 (also called hydrogen), hydrogen 2 (also called deuterium) and hydrogen 3 (also called tritium). Hope this helps. Scott D. Scott MacKenzie, PhD Heat Treating (Aluminum and Steel) Quenching (Water, Polymer, Oil, Salt and Mar-Tempering) Link to comment Share on other sites More sharing options...
Alan Longmire Posted September 23, 2007 Share Posted September 23, 2007 To add to that: an imbalance between the number of protons to neutrons generally produces radiation. This can be anything from low-level mostly harmless alpha particles up to and including hard gamma rays. Do some more research and make sure you're not getting anything very hot! Hot stuff is supposed to be tightly controlled, I know, but it still gets out. Most radiation is pretty harmless also, but some types and strengths are more iffy than others. No need to get hysterical, but do be careful. Link to comment Share on other sites More sharing options...
Bennett Posted September 24, 2007 Author Share Posted September 24, 2007 (edited) Th Jerry Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
Bennett Posted October 4, 2007 Author Share Posted October 4, 2007 (edited) He Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
kb0fhp Posted October 5, 2007 Share Posted October 5, 2007 the intragranular ferrite plates that they speak of - as best as I can tell, are small islands of ferrite with in the grain - new grains have nucleated of ferrite. Based on the paper, it increases toughness - think of ferrite as soft marshmallows in the matrix. The ferrite absorbs the shock - effectively requiring more energy to fracture.... At least that was the way I understood it. Scott D. Scott MacKenzie, PhD Heat Treating (Aluminum and Steel) Quenching (Water, Polymer, Oil, Salt and Mar-Tempering) Link to comment Share on other sites More sharing options...
Bennett Posted October 5, 2007 Author Share Posted October 5, 2007 (edited) [qu Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
Bennett Posted October 5, 2007 Author Share Posted October 5, 2007 (edited) Rey Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
Bennett Posted October 9, 2007 Author Share Posted October 9, 2007 (edited) We Edited April 29, 2011 by Bennett Link to comment Share on other sites More sharing options...
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