Doug,
In fact, you have a few questions in there. Steel is an alloy of iron, carbon, molybdenum, and chromium, plus traces of other elements, if I recall correctly. Its properties vary considerably depending on the manufacturing method - hot rolled, cold rolled, plate, rod, wire, etc. So we have both composition and manufacturing process which affect the properties of the product.
First, there is a greater number of standard alloys which were just not present fifty years ago. The ASM/ASTM red books (my monitor's being held up by vol. 8 - materials testing) define the properties of these alloys and the manner in which they are to be produced and tested. In this sense, when Ford's or GM's engineers order a certain steel alloy, they order a material with better-defined and better-constrained properties than their forebears did fifty years ago.
Second, there is the matter of quality control. Most steel plants use Japanese-style methods (that is, Demingist or Juranist methods - american by way of Japan) to implement quality control in their manufacturing process. As such, there is much less variance within and between lots of steel. So the steel itself is of better consistency, even if it were the exact same steel.
(Sidebar: In Demingist or Juranist quality methods, the process, not the product, is addressed and fixed. Very few products are tested at the end of a production line any more: it's too expensive and unnecessary.)
Quality control also improves process efficiency, which is why many long-term contracts with big automakers actually get cheaper over time, typically a decrease of 1 to 2.5 percent per annum after the first three years. They assume that the influx of cash from these big orders has let the plant get their lines in order and realize efficiencies over time.
Third, manufacturing proper is much improved. No doubt the Firestone plant had a QA/QC program, which, with the departure of their union staff, went out the window. It's actually very important to minimize turnover in order to implement a philosophy such as kaizen (continuous self-improvement). I daresay they made token efforts to hold the line on quality, not improve it but just try to hold it steady, and hoped that nothing really bad would happen.
No doubt Firestone made money in the short term by reducing salaries - they used scab labour and management to run their lines, after all. However, I doubt that they made a dime once the costs of recall are factored in. They probably lost a mint, and no doubt they've lost all their hard-won goodwill with Ford as well.
Finally, if you get the chance to tour a modern steel mill, do go. It's a fascinating experience.
Marco
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> | Now if you think it strange that <
> | mice should elect a government made <
> Marco Anglesio | up of cats, you just look at the <
> mpa at the-wire.com | history of Canada for the last 90 years <
> http://www.the-wire.com/~mpa | and maybe you'll see that they weren't <
> | any stupider than we are. <
> | --Tommy Douglas <
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