Plow Steel: Composition and Numerical Designation?

My grandfather was a blacksmith and made plows for the local farmers (pulled by tractor). When he was finished shaping the plows, he melted a very hard cast iron on the edge to improve their wear.

By now, I assume they use tungsten filler rod to coat the edge.

I suppose I should be a little more descriptive. All that large earth moving equipment that have shovels and teeth are visited by a welder that has tungsten rods - a hollow rod filled with tungsten, which is deposited on edges and teeth through an arc welding process. This makes the equipment last a heck of a lot longer. As the tungsten eventually wears off, the welder is invited out once again to make his coating.

Just google "plow steel" and you'll probably learn more about the subject than you care to know (including, of course, that the term doesn't involve plows). The strengths you've noted are grades of stranded wire rope of various stranding and tensile strength. Typically, plow steel strand encompasses the carbon range of 0.5 - 0.95%.

Oops!