Microalloyed medium carbon steels
1 Scope
This standard specifies the terms and definitions, classification, ordering, shape, dimensions and tolerances, technical requirements, test methods, inspection rules, packaging, marking and quality certificates of microalloyed medium carbon steels.
This standard is applicable to hot rolled steel and bright steel of microalloyed medium carbon steels (hereinafter referred to as the steel).
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 223.5 Steel and iron—Determination of acid-soluble silicon and total silicon content—Reduced molybdosilicate spectrophotometric method (GB/T 223.5—2008, ISO 4829-1:1986, ISO 4829-2;1988, MOD)
GB/T 223.11 Iron, steel and alloy—Determination of chromium content—Visual titration or potentiometric titration method (GB/T 223.11-2008, ISO 4937:1986, MOD)
GB/T 223.16 Methods for chemical analysis of iron, steel and alloy—The chromotropic acid photometric method for the determination of titanium content
GB/T 223.18 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 Iron, steel and alloy—Determination of nickel content—The dimethylglyoxime spectrophotometric method (GB/T 223.23-2008, ISO 4939:1984, MOD)
GB/T 223.26 Iron, steel and alloy—Determination of molybdenum content—The thiocyanate spectrophotometric method
GB/T 223.37 Methods for chemical analysis of iron, steel and alloy—The indophenol blue photometric methods for the determination of nitrogen content after distillation separation
GB/T 223.40 Iron, steel and alloy—Determination of niobium content by the sulphochlorophenol S spectrophotometric method
GB/T 223.58 Methods for chemical analysis of iron, steel and alloy—The sodium arsenite-sodium nitrite titrimetric method for the determination of manganese content
GB/T 223.59 Iron, steel and alloy—Determination of phosphorus content—Bismuth phosphomolybdate blue spectrophotometric method and antimony phosphomolybdate blue spectrophotometric method
GB/T 223.68 Methods for chemical analysis of iron, steel and alloy—The potassium iodate titration method after combustion in the pipe furnace for the determination of sulfur content (GB/T 223.68-1997, ISO 671:1982, MOD)
GB/T 223.69 Iron, steel and alloy—Determination of carbon contents—Gas-volumetric method after combustion in the pipe furnace
GB/T 223.76 Methods for chemical analysis iron, steel and alloy—The flame atomic absorption spectrometric method for the determination of vanadium content (GB/T 223.76-1994, ISO 9647:1989, MOD)
GB/T 223.78 Methods for chemical analysis of iron, steel and alloy—Curcumin spectrophotometric method for the determination of boron content (GB/T 223.78-2000, ISO 10153:1997, IDT)
GB/T 224-2008 Determination of depth of decarburization of steels (ISO 3887:2003, MOD))
GB/T 226 Test method for macrostructure and defect of steel by etching
GB/T 228.1 Metallic materials—Tensile testing—Part 1: Method of test at room temperature (GB/T 228.1-2010, ISO 6892-1:2009, MOD)
GB/T 229 Metallic materials—Charpy pendulum impact test method (GB/T 229-2007, ISO 148-1:2006, MOD)
GB/T 231.1 Metallic materials—Brinell hardness test—Part 1: Test method (GB/T 231.1-2009, ISO 6506-1:2005, MOD)
GB/T 702-2008 Hot-rolled steel bars—Dimensions, shape, weight and tolerances (ISO 1035-1:1980, ISO 1035-2:1980, ISO 1035-4:1982, MOD)
GB/T 1979 Standard diagrams for macrostructure and defect of structural steels
GB/T 2101 General requirement of acceptance, packaging, marking and certification for section steel
GB/T 2975 Steel and steel products—Location and preparation of samples and test pieces for mechanical testing (GB/T 2975-1998, eqv ISO 377:1997)
GB/T 3207-2008 Bright steel
GB/T 4162 Forged and rolled steel bars—Method for ultrasonic testing
GB/T 4336 Standard test method for spark discharge atomic emission spectrometric analysis of carbon and low—Alloy steel (Routine method)
GB/T 6394 Metal-methods for estimating the average grain size
GB/T 7736 Ultrasonic inspecting method for macro-structure and imperfection of steel
GB/T 10561-2005 Steel—Determination of content of nonmetallic inclusions—Micrographic method using standards diagrams (ISO 4967:1998, IDT)
GB/T 13298 Inspection methods of microstructure for metals
GB/T 13299 Steel—Determination of microstructure
GB/T 13304.1 Steels classification—Part 1: Classification of according to chemical composition (GB/T 13304.1-2008, ISO 4948-1:1982)
GB/T 15574 Steel products—Vocabulary (GB/T 15574-2016, ISO 6929:2013, MOD)
GB/T 17505 Steel and steel products—General technical delivery requirements (GB/T 17505-2016, ISO 404:2013, MOD)
GB/T 18253 Steel and steel products—Types of inspection documents (GB/T 18253-2002, ISO 10474:1991, MOD)
GB/T 20066 Steel and iron—Sampling and preparation of samples for the determination of chemical composition (GB/T 20066-2006, ISO 14284: 1996, IDT)
GB/T 20123 Steel and iron—Determination of total carbon and sulfur content—Infrared absorption method after combustion in an induction furnace (routine method) (GB/T 20123-2006, ISO 15350:2000, IDT)
GB/T 20124 Steel and iron—Determination of nitrogen content—Thermal conductimetric method after fusion in a current of inert gas (routine method) (GB/T 20124-2006, ISO 15351:1999, IDT)
GB/T 20125 Low-alloy steel—Determination of multi-element contents—Inductively coupled plasma atomic emission spectrometric method
GB/T 28300 Surface quality classes for hot-rolled bars and rods technical delivery conditions
3 Terms and definitions
For the purposes of this document, the terms and definitions specified in GB/T 15574 and GB/T 13304.1 as well as the following apply.
3.1
microalloyed medium carbon steels
high-quality or special-quality structural steel which can achieve or approach the mechanical properties of quenched and tempered steel by means of strengthening and toughening methods such as microalloying, controlled rolling (forging) and controlled cooling
4 Classification
4.1 Steels are classified, by microstructure, as
a) ferrite-pearlite steel;
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Classification
5 Ordering
6 Dimensions, shape and tolerances
7 Technical requirements
8 Test methods
9 Inspection rules
10 Packaging, marking and quality certificate
Annex A (Informative) Comparison of clause numbers of this standard and those of ISO 11692:1994
Annex B (Informative) Technical differences between this standard and ISO 11692:1994 and their reasons
Annex C (Informative) Comparison between designation of this standard and designation of ISO 11692:1994
Microalloyed medium carbon steels
1 Scope
This standard specifies the terms and definitions, classification, ordering, shape, dimensions and tolerances, technical requirements, test methods, inspection rules, packaging, marking and quality certificates of microalloyed medium carbon steels.
This standard is applicable to hot rolled steel and bright steel of microalloyed medium carbon steels (hereinafter referred to as the steel).
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 223.5 Steel and iron—Determination of acid-soluble silicon and total silicon content—Reduced molybdosilicate spectrophotometric method (GB/T 223.5—2008, ISO 4829-1:1986, ISO 4829-2;1988, MOD)
GB/T 223.11 Iron, steel and alloy—Determination of chromium content—Visual titration or potentiometric titration method (GB/T 223.11-2008, ISO 4937:1986, MOD)
GB/T 223.16 Methods for chemical analysis of iron, steel and alloy—The chromotropic acid photometric method for the determination of titanium content
GB/T 223.18 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 Iron, steel and alloy—Determination of nickel content—The dimethylglyoxime spectrophotometric method (GB/T 223.23-2008, ISO 4939:1984, MOD)
GB/T 223.26 Iron, steel and alloy—Determination of molybdenum content—The thiocyanate spectrophotometric method
GB/T 223.37 Methods for chemical analysis of iron, steel and alloy—The indophenol blue photometric methods for the determination of nitrogen content after distillation separation
GB/T 223.40 Iron, steel and alloy—Determination of niobium content by the sulphochlorophenol S spectrophotometric method
GB/T 223.58 Methods for chemical analysis of iron, steel and alloy—The sodium arsenite-sodium nitrite titrimetric method for the determination of manganese content
GB/T 223.59 Iron, steel and alloy—Determination of phosphorus content—Bismuth phosphomolybdate blue spectrophotometric method and antimony phosphomolybdate blue spectrophotometric method
GB/T 223.68 Methods for chemical analysis of iron, steel and alloy—The potassium iodate titration method after combustion in the pipe furnace for the determination of sulfur content (GB/T 223.68-1997, ISO 671:1982, MOD)
GB/T 223.69 Iron, steel and alloy—Determination of carbon contents—Gas-volumetric method after combustion in the pipe furnace
GB/T 223.76 Methods for chemical analysis iron, steel and alloy—The flame atomic absorption spectrometric method for the determination of vanadium content (GB/T 223.76-1994, ISO 9647:1989, MOD)
GB/T 223.78 Methods for chemical analysis of iron, steel and alloy—Curcumin spectrophotometric method for the determination of boron content (GB/T 223.78-2000, ISO 10153:1997, IDT)
GB/T 224-2008 Determination of depth of decarburization of steels (ISO 3887:2003, MOD))
GB/T 226 Test method for macrostructure and defect of steel by etching
GB/T 228.1 Metallic materials—Tensile testing—Part 1: Method of test at room temperature (GB/T 228.1-2010, ISO 6892-1:2009, MOD)
GB/T 229 Metallic materials—Charpy pendulum impact test method (GB/T 229-2007, ISO 148-1:2006, MOD)
GB/T 231.1 Metallic materials—Brinell hardness test—Part 1: Test method (GB/T 231.1-2009, ISO 6506-1:2005, MOD)
GB/T 702-2008 Hot-rolled steel bars—Dimensions, shape, weight and tolerances (ISO 1035-1:1980, ISO 1035-2:1980, ISO 1035-4:1982, MOD)
GB/T 1979 Standard diagrams for macrostructure and defect of structural steels
GB/T 2101 General requirement of acceptance, packaging, marking and certification for section steel
GB/T 2975 Steel and steel products—Location and preparation of samples and test pieces for mechanical testing (GB/T 2975-1998, eqv ISO 377:1997)
GB/T 3207-2008 Bright steel
GB/T 4162 Forged and rolled steel bars—Method for ultrasonic testing
GB/T 4336 Standard test method for spark discharge atomic emission spectrometric analysis of carbon and low—Alloy steel (Routine method)
GB/T 6394 Metal-methods for estimating the average grain size
GB/T 7736 Ultrasonic inspecting method for macro-structure and imperfection of steel
GB/T 10561-2005 Steel—Determination of content of nonmetallic inclusions—Micrographic method using standards diagrams (ISO 4967:1998, IDT)
GB/T 13298 Inspection methods of microstructure for metals
GB/T 13299 Steel—Determination of microstructure
GB/T 13304.1 Steels classification—Part 1: Classification of according to chemical composition (GB/T 13304.1-2008, ISO 4948-1:1982)
GB/T 15574 Steel products—Vocabulary (GB/T 15574-2016, ISO 6929:2013, MOD)
GB/T 17505 Steel and steel products—General technical delivery requirements (GB/T 17505-2016, ISO 404:2013, MOD)
GB/T 18253 Steel and steel products—Types of inspection documents (GB/T 18253-2002, ISO 10474:1991, MOD)
GB/T 20066 Steel and iron—Sampling and preparation of samples for the determination of chemical composition (GB/T 20066-2006, ISO 14284: 1996, IDT)
GB/T 20123 Steel and iron—Determination of total carbon and sulfur content—Infrared absorption method after combustion in an induction furnace (routine method) (GB/T 20123-2006, ISO 15350:2000, IDT)
GB/T 20124 Steel and iron—Determination of nitrogen content—Thermal conductimetric method after fusion in a current of inert gas (routine method) (GB/T 20124-2006, ISO 15351:1999, IDT)
GB/T 20125 Low-alloy steel—Determination of multi-element contents—Inductively coupled plasma atomic emission spectrometric method
GB/T 28300 Surface quality classes for hot-rolled bars and rods technical delivery conditions
3 Terms and definitions
For the purposes of this document, the terms and definitions specified in GB/T 15574 and GB/T 13304.1 as well as the following apply.
3.1
microalloyed medium carbon steels
high-quality or special-quality structural steel which can achieve or approach the mechanical properties of quenched and tempered steel by means of strengthening and toughening methods such as microalloying, controlled rolling (forging) and controlled cooling
4 Classification
4.1 Steels are classified, by microstructure, as
a) ferrite-pearlite steel;
Contents of GB/T 15712-2016
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Classification
5 Ordering
6 Dimensions, shape and tolerances
7 Technical requirements
8 Test methods
9 Inspection rules
10 Packaging, marking and quality certificate
Annex A (Informative) Comparison of clause numbers of this standard and those of ISO 11692:1994
Annex B (Informative) Technical differences between this standard and ISO 11692:1994 and their reasons
Annex C (Informative) Comparison between designation of this standard and designation of ISO 11692:1994