从焊接化学冶金与焊接物理冶金入手,阐述了7FDL—16型柴油机用的组焊式气缸盖在焊接传热、焊接热循环、焊缝及熔合区性能、焊接热影响区特性及焊接冶金缺陷诸方面的问题;指出了美国 GE 公司采用组焊式结构的气缸盖并非是一种最佳方案。文中介绍了国产化整铸式合金钢气缸盖的试制及运用概况及整铸式气缸盖焊堵处焊缝和气门座口焊缝的焊接冶金特性。 Starting from welding chemistry metallurgy and welding physics metallurgy, this paper expounds the welding heat flux, welding heat cycle, weld seam and fusion zone performance, weld heat affected zone characteristics and welding metallurgy defects of 7FDL-16 diesel engine. It is pointed out that the cylinder head of welding structure used by American GE Company is not the best solution. This paper introduces the trial manufacture and application overview of domestically made cast alloy steel cylinder heads and the welding metallurgy characteristics of welds and valve seat welds in the cast-in-place cylinder head weld block.