I do not think so. You just need enough argon to exclude oxygen. If you can afford to add it to your system oil free nitrogen makes a good back up gas ( for the back of the weld) and is much cheaper than argon. If you can get it as a mixed gas, argon and nitrogen, it works good as a cover gas.
Normally getting too hot has to with thickness differences in material or retained heat as you continue the weld. That is one thing that a foot control is great for, because you can vary the current as you weld. If you have an air cooled torch that might also be a factor. I do not know for sure, all I have ever used are water cooled 100% duty cycle torches.