GB/T 8731-2025 Free-cutting structural steels

GB/T 8731-2008 Free-cutting structural steel

GB/T 223.78-2000 Methods for chemical analysis of iron,steel and alloy—Curcumin spectrophotometric method for the determination of boron content GB/T 223.79-2007 Iron and steel—Determination of multi-element contents—X-ray fluorescence spectrometry(Routine method) GB/T 223.80-2007 Iron,steel and alloy—Determination of trace bismuth and arsenic contents—Hydride generation-atomic fluorescence spectrometric method GB/T 223.81-2007 Iron,steel and alloy—Determination of total aluminum and total boron contents—Microwave digestion-inductively coupled plasma mass spectrometric method GB/T 223.82-2007 Steel and iron—Determination of hydrogen content—Inert gas impulse fusion heat conductivity method GB/T 223.82-2018 Steel and iron—Determination of hydrogen content—Thermal conductivity/infrared method after fusion under inert gas GB/T 223.83-2009 Steel and iron—Determination of high sulfur content—Infrared absorption method after combustion in an induction furnace GB/T 223.84-2009 Steel and iron—Determination of titanium content—Diantipyrylmethane spectrophotometric method GB/T 223.85-2009 Steel and iron—Determination of sulfur content—Infrared absorption method after combustion in an induction furnace GB/T 223.86-2009 Steel and iron—Determination of total carbon content—Infrared absorption method after combustion in an induction furnace GB/T 223.87-2018 Iron, steel and alloy—Determination of calcium and magnesium—Inductively coupled plasma mass spectrometric method GB/T 223.88-2019 Iron,steel and alloy—Determination of calcium and magnesium contents—Inductively coupled plasma atomic emission spectrometric method GB/T 223.89-2019 Iron,steel and alloy—Determination of tellurium content—Hydride generation-atomic fluorescence spectrometric method GB/T 223.90-2021 Iron,steel and alloy—Determination of silicon content—Inductively coupled plasma atomic emission spectrometric method GB/T 223.91-2021 Iron,steel and alloy—Determination of copper—2,2′-Biquinoline spectrophotometric method GB/T 223.92-2023 Iron, steel and alloy—Determination of lanthanum, cerium, praseodymium, neodymium and samarium content—Inductively coupled plasma mass spectrometry GB/T 224-1987 Determination of depth of decarburization of steel GB/T 224-2008 Determination of depth of decarburization of steels GB/T 224-2019 Determination of the depth of decarburization of steels GB/T 226-1991 Etch test for macrostructure and defect of steels GB/T 226-2015 Test method for macrostructure and defect of steel by etching GB/T 228.1-2010 Metallic materials—Tensile testing—Part 1:Method of test at room temperature GB/T 228.1-2021 Metallic materials—Tensile testing—Part 1:Method of test at room temperature GB/T 229-1994 Metallic materials—Charpy notch impact test GB/T 229-2007 Metallic materials—Charpy pendulum impact test method GB/T 229-2020 Metallic materials—Charpy pendulum impact test method GB/T 231.1-2002 Metallic materials—Brinell hardness test—Part 1:Test method GB/T 231.1-2009 Metallic materials—Brinell hardness test—Part 1:Test method GB/T 231.1-2018 Metallic materials—Brinell hardness test—Part 1:Test method GB/T 247-1997 General rule of acceptance, package, mark and certification for steel plates(sheets) and strips GB/T 247-2008 General rule of package,mark and certification for steel plates(sheets)and strips GB/T 247-2025 General rules of package, mark and certification for steel plate, sheet and strip GB/T 342-2017 Dimension,shape,mass and tolerance of cold-drawn round,square and hexagonal steel wires GB/T 702-2017 Hot-rolled steel bars—Dimensions,shape,weight and tolerances GB/T 905-1994 Dimension, shape, weight and tolerance for cold-drawn round, square and hexagonal steels GB/T 908-2019 Forged bars for dimensions,shape,weight and tolerances GB/T 1979-2001 Standard diagrams for macrostructure and defect of structural steels GB/T 1979-2025 Evaluation of macrostructural defects in structural steels—Acid etching method and ultrasonic testing method GB/T 2101-1989 General requirements of acceptance, packaging, marking and certification for section steel GB/T 2101-2008 General requirement of acceptance,packaging,marking,and certification for section steel GB/T 2101-2017 General requirement of acceptance,packaging,marking and certification for section steel GB/T 2103-1988 General provisions for checking, packing, marking and quality certification of steel wire GB/T 2103-2008 General requirements for acceptance,packing,marking and quality certification of steel wire GB/T 2975-1998 Steel and steel products—Location and preparation of test pieces for mechanical testing GB/T 2975-2018 Steel and steel products—Location and preparation of samples and test pieces for mechanical testing GB/T 3207-1988 Bright steel GB/T 3207-2008 Bright steel GB/T 3207-2025 Bright steel GB/T 4162-1991 Forged and rolled steel bars—Method for ultrasonic examination GB/T 4162-2008 Forged and rolled steel bars—Method for ultrasonic testing GB/T 4162-2022 Method for ultrasonic testing of forged and rolled steel bars GB/T 4336-2002 Standard test method for spark discharge atomic emission spectrometric analysis of carbon and low-Alloy steel(routine method) GB/T 4336-2016 Carbon and low-alloy steel—Determination of multi-element contents—Spark discharge atomic emission spectrometric method (routine method) GB/T 6402-1991 Steel forgings—Method for ultrasonic examination GB/T 6402-2008 Steel forgings—Method for ultrasonic testing GB/T 6402-2024 Method for ultrasonic testing of steel forgings GB/T 8170-1987 Rules for rounding off of numberical values GB/T 8170-2008 Rules of rounding off for numerical values & expression and judgement of limiting values GB/T 10561-1989 Steel—Determination of content of non-metallic inclusion—Micrographic method using standard diagrams GB/T 10561-2005 Steel—Determination of content of nonmetallic inclusions—Micrographic method using standards diagrams GB/T 10561-2023 Determination of content of nonmetallic inclusions in steel—Micrographic method using standard diagrams GB/T 13298-1991 Metal—Inspection method of microstructure GB/T 13298-2015 Inspection methods of microstructure for metals GB/T 13299-1991 Steel—Determination of microstructure GB/T 13299-2022 Determination of free cementite,pearlite and Widmanstaten structure in steel GB/T 14981-2009 Dimension,shape,mass and tolerance for hot-rolled round wire rod GB/T 15711-1995 Steel products—Method for etch test of tower sample GB/T 15711-2018 Inspection of non-metallic inclusions of steel—Etching test method of tower samples GB/T 17505-1998 Steel and steel products General technical delivery requirements GB/T 17505-2016 Steel and steel products—General technical delivery requirements GB/T 20066-2006 Steel and iron—Sampling and preparation of samples for the determination of chemical composition GB/T 20123-2006 Steel and iron—Determination of total carbon and sulfur content Infrared absorption method after combustion in an induction furnace (routine method) GB/T 20125-2006 Low-alloy steel—Determination of multi-element contents—Inductively coupled plasma atomic emission spectrometric method GB/T 20126-2006 Unalloyed Steel—Determination of low carbon content—Part 2:Infrared absorption method after combustion in an induction furnace(With preheating) GB/T 20566-2006 Terminology of steel and alloy GB/T 22368-2008 Low-alloy steel—Determination of multi-element contents—Glow discharge optical emission spectrometry(Routine method) GB/T 28300-2012 Surface quality classes for hot-rolled bars and rods technical delivery conditions GB/T 28300-2025 Surface quality classes for hot-rolled bars and wire rod GB/T 34474.1-2017 Determination of banded structure of steel—Part 1:Micrographic method using standards diagrams