Ultrasonic Testing & Grain-flow Inspection of Forgings
锻件超声波探伤与流线检验
标签：超声探伤, 金属流线, 宏观浸蚀, 电导率
重要铜锻件（导电件、船用件）内部质量用超声探伤：铜声衰减小但晶粒偏粗，选 2.25–5 MHz 直探头按 20×20 mm 网格扫查，以平底孔当量 Ø1.2–2.0 mm 判收判废。锻造流线用低倍浸蚀验证：横截面样经三氯化铁盐酸溶液腐蚀 15–30 s，流线应沿锻件外形连续闭合，无穿流与涡流。电工件另做涡流法电导率测试（ASTM E1004），IACS ≥95% 为合格线。三项结果与炉批号一并记入质保书，出口船检订单必查。
Critical copper forgings (electrical, marine) get ultrasonic testing: copper grain coarseness calls for 2.25–5 MHz straight-beam probes scanning a 20×20 mm grid, judged against flat-bottom-hole equivalents of Ø1.2–2.0 mm. Grain flow is verified by macroetch: a cross-section etched 15–30 s in ferric-chloride/hydrochloric solution should show flow lines closing continuously around the outline, with no bleed-through or swirl. Electrical parts add eddy-current conductivity testing per ASTM E1004 with an IACS ≥95% pass line. All three results go on the certificate tied to heat numbers — mandatory for marine-surveyed exports.