GB/T 35840.4-2020 Steels for plastic mould—Part 4:Pre-hardening steel plate

GB/T 709-2019 Dimension,shape,weight and tolerance for hot-rolled steel strip,plate and sheet GB/T 2970-2016 Method for ultrasonic testing of thicker steel plates GB/T 10561-2005 Steel—Determination of content of nonmetallic inclusions—Micrographic method using standards diagrams GB/T 223.5-1997 Methods for chemical analysis of iron,steel and alloy—The reduced molybdosilicate spectro photometric method for the determination of acid-soluble silicon content GB/T 223.5-2008 Steel and iron—Determination of acid-soluble silicon and total silicon content—Reduced molybdosilicate spectrophotometric method GB/T 223.8-2000 Methods for chemical analysis of iron,steel and alloy The sodium fluoride separation—EDTA titration method for the determination of aluminium content GB/T 223.11-1991 Methods for chemical analysis of iron, steel and alloy The ammonium persulfate oxidation volumetric method for the determination of chromium content GB/T 223.11-2008 Iron,steel and alloy—Determination of chromium content—Visual titration or potentiometric titration method GB/T 223.14-2000 Methods for chemical analysis of iron,steel and alloy The N-benzoy-N-phenylhydroxylamine extraction photometric method for the determination of vanadium content GB/T 223.18-1994 Methods for chemical analysis of iron, steel and alloy The sodium thiosulfate separation iodimetric method for the determination of cupper content GB/T 223.23-1994 Methods for chemical analysis of iron, steel and alloy—The dimethylglyoxime spectrophotometric method for the determination of nickel content GB/T 223.23-2008 Iron,steel and alloy—Determination of nickel content—The dimethylglyoxime spectrophotometric method GB/T 223.25-1994 Methods for chemical analysis of iron, steel and alloy The dimethylglyoxime gravimetric method for the determination of nickel content GB/T 223.26-1989 Methods for chemical analysis of iron, steel and alloy The thiocyanate direct photometric method for the determination of molybdenum content GB/T 223.26-2008 Iron,steel and alloy—Determination of molybdenum content—The thiocyanate spectrophotometric method GB/T 223.59-2008 Iron,steel and alloy—Determination of phosphorus content—Bismuth phosphomolybdate blue spectrophotometric method and antimony phosphomolybdate blue spectrophotometric method GB/T 223.69-1997 Methods for chemical analysis of iron,steel and alloy The gas- volumetric method after combustion in the pipe furnace for the determination of carbon content GB/T 223.69-2008 Iron,steel and alloy—Determination of carbon contents—Gas-volumetric method after combustion in the pipe furnace GB/T 223.72-1991 Methods for chemical analysis of iron, steel and alloy—The alumina chromatographic separation-barium sulfate gravimetric method for the determination of sulphur content GB/T 223.72-2008 Iron,steel and alloy—Determination of sulfur content—Gravimetric method 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 230.1-2004 Metallic Rockwell hardness test—Part1:Test method(scales A、B、C、D、E、F、G、H、K、N、T) GB/T 230.1-2009 Metallic materials—Rockwell hardness test—Part 1:Test method(scales A、B、C、D、E、F、G、H、K、N、T) GB/T 230.1-2018 Metallic materials—Rockwell 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 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 6394-2002 Metal-methods for estimating the average grain size GB/T 6394-2017 Determination of estimating the average grain size of metal 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 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 223.53-1987 Methods for chemical analysis of iron，steel and alloy--The flame atomic absorption spectrophotometric method for the determination of copper content GB/T 223.58-1987 Methods for chemical analysis of iron，steel and alloy--The extraction-absorption catalytic polarographic method for the determination of manganese content GB/T 247-2025 General rules of package, mark and certification for steel plate, sheet and strip GB/T 223.8-2025 Iron,steel and alloy—Determination of aluminium content—Titrimetric method and spectrophotometric method GB/T 223.11-2025 Iron, steel and alloy—Determination of chromium content—Titrimetric method and spectrophotometric method