quantify this-The difference between 70000 psi and 60000psi

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I have often wondered what do you gain when you use a 60 series rod vs a 70 series rod.  Does anybody have an idea how to describe or example of the difference?I am not considered with all of the different variables involved.  I am more interested in a physical  reference of the 10000 psi difference?
Reply:You don't gain a thing if you are using just mild steel plate.  If your weld metal was 100 thousand ultimate tensile strength it would make little difference if the parent metal was only 60,000 UTS.  There are other things to consider such as yield strength and impact strength.  With steel it is typical that the weld metal is as good as the parent metal or stronger.     With aluminum it is common for the weld metal to not be a strong as the parent metal.   It becomes important to use 80,000 tensile rod when you join alloys such as T1 which is used for wear surfaces and cuttting edges ... as well as armour plate.
Reply:Also, keep in mind that the ACTUAL tensile strength of most quality rods far exceed the minimum AWS classification.Many 60-series rods do have closer to 70,000 PSI tensile strength anyway.
Reply:The way I see it, 7018 has more flexability.  OK, ductility than the 6010, or 6013.  Stick a 6010 to the work surface, bend it back and forth.  See how it breaks off.  Do the same with 7018.This may not apply, because you asked about 60K vs, 70K, not 10 vs 18.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Weld a piece of AR-400 with 7018 and then with 6010 the 6010 will crack everytime.Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:The 60XX rods tend to be less expensive, run easier and be more forgiving while running the weld than the corresponding 70XX (or 80X, or 90XX, or .....) rods. If 6010 is acceptable, then use it over 7010 for all of the above reasons. Ditto for the '18 electrodes... 7018 is the least expensive and tends to be the easest running. You really can't compare properties between classes (6010 to 7018 isn't a reasonable comparison-- the rods have different purposes and properties. 6010 to 7010 is fair)The higher strength versions are more highly alloyed, and may have flux modifications to make the required strength for the weld deposit. Both of these changes affect the ease of use as well as the price. Another concern going up the scale is the difficulty of controlling the as-welded properties of the higher strength wires. Not a real issue with the 60XX and 70XX types, but don't succum to the 'if 70KSI is good, then 100KSI is better' syndrome.  The higher strength rods are more sensetive to cracking, among other things, and overmatching fillers may, for example, provide excessive restraint at the weld and present a stress riser to lead to failure later. And, you need just as much weld as with a matching filler, since the base metal is no stronger and you still need sufficient tie in.Do not mistake the properties of the rod as supplied for the characteristics as welded. As supplied, the rods are, well, rods. There will be various drawn-wire 'features' that will not be present in the weld metal, as the weld metal is pretty much fresh cast material, with properties based on the alloy, base metal, flux treatment, cooling rate, etc.
Reply:Originally Posted by tapwelderI have often wondered what do you gain when you use a 60 series rod vs a 70 series rod.  Does anybody have an idea how to describe or example of the difference?I am not considered with all of the different variables involved.  I am more interested in a physical  reference of the 10000 psi difference?
Reply:Going back to the '60's nearly everything was welded with 60xx and most of it's still standing.
Reply:Originally Posted by cliveGoing back to the '60's nearly everything was welded with 60xx and most of it's still standing.