用40Cr制造齿轮的典型热处理为（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24890' and id < 2124361 and id<>'2124361' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24890' and id > 2124361 and id<>'2124361' order by id asc limit 5