Brittle tempering kub ntau raws li cov raj precision tuaj yeem muab faib ua qhov qis thiab siab kub temper brittleness temper brittleness.

Tom qab tempering brittleness precision tube alloy steel quenched martensite ntawm qhov kub ntawm 250 ~ 400 ℃ tempered steel embrittlement uas lub nkig ductile hloov kub nce ho. Nws tshwm sim tsuas yog nyob rau hauv steel alloy structural steel thiab low-alloy siab precision raj. Twb tau nkig tawg precision raj yog intergranular puas los yog quasi-cleavage thiab intergranular puas sib xyaw. Ua rau tempering brittleness, feem ntau xav txog: (1) thiab cementite thaum tempering rau ib daim ntawv nyob rau hauv thawj austenite grain ciam teb, ua rau grain ciam teb embrittlement yog ze ze. (2) impurity ntsiab xws li phosphorus nyob rau hauv austenite grain ciam cais kuj yog ib qho ntawm cov laj thawj tempering brittleness. Phosphorus tsawg dua 0.005% siab purity precision raj tsis tsim qhov kub thiab txias tempering brittleness. Phosphorus tshwm sim nyob rau hauv austenite grain ciam teb thaum hluav taws kub cua sov cais tom qab quenching khaws cia. Phosphorus nyob rau hauv austenite grain ciam ciam sib cais thiab cementite thaum tempering nyob rau hauv lub qub austenite grain ciam teb, ob yam no ua rau lub intergranular brittle puas, pab rau tempering brittleness tshwm sim.

Precision raj alloying cov ntsiab lus muaj kev cuam tshuam ntau dua rau qhov qis-kub tempering brittleness. Chromium thiab manganese txhawb kev sib cais ntawm impurity ntsiab xws li phosphorus nyob rau hauv lub austenite grain ciam teb, yog li ua rau tempering brittleness, tungsten thiab vanadium yeej tseem ceeb tsis muaj kev cuam tshuam, molybdenum deteriorate lub toughness ntawm ib tug brittle hloov kub tempering precision raj, tab sis tsis txaus inhibition tempering brittleness. . Thaum silicon tuaj yeem ncua tempered cementite nag lossis daus, uas ua rau muaj qhov kub thiab txias, nws tuaj yeem txhim kho qhov precision raj tempering kub brittleness tshwm sim.