摘要 |
A method of cracking bearing assembles including the steps of (a) forming a ductile metal (steel, aluminum or titanium) connecting rod in one piece (e.g., by hot forging) having an annular wall defining a crankshaft opening with preformed surface crevices for guiding the initiation of a cracking plane that extends across the crank opening; (b) charging (i.e., for about 40 seconds) the region of such wall along at least one portion of the cracking plane with hydrogen by means of an electrolytic cell or by means of reacting the metal rod with a strong acid (e.g., concentrated sulfuric) to cause hydrogen to dissolve in the metal to facilitate hydrogen stress cracking thereat, with or without the imposition of static mechanical tensile loading at such crevices (i.e., for about 40 seconds) of a magnitude insufficient to cause yielding of the metal; and (c) prolonging, increasing, or imposing the static mechanical loading (i.e., for another 40 seconds) at the crevices to effect fracture across the entire cracking plane and thereby separate the connecting rod into a cap and body with rough, fractured mating surfaces.
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