According to UNS Unified Numbering System2011
Designation of CARBON&ALLOY
STEEL
Introduction
• The UNS number (short for Unified Numbering System for Metals and Alloys) is designated by a letter followed by five numbers. It is a composition-based system of commercial materials and does not guarantee any performance specifications or exact composition with impurity limits.
ASTM (American Society for Testing and Materials) and SAE (Society of Automotive Engineer) began discussion about UNS in 1967 to make project program deal with 3 :
Continue introduction
• 1- Simplify the many systems of designation are different• 2- Give trade names a general number, help when one alloy
that product in several companies have different trade names.
• 3-Computrized the new system • Activity of US army with this study resulted to the
development of UNS in 1969; the first edition of UNS for metals and alloys was in 1975.
Overview of the UNS system• Axxxxx - Aluminum Alloys• Cxxxxx - Copper Alloys, including Brass and Bronze• Fxxxxx - Iron, including Ductile Irons and Cast Irons• Gxxxxx - Carbon and Alloy Steels• Hxxxxx - Steels - AISI H Steels• Jxxxxx - Steels - Cast• Kxxxxx - Steels, including Maraging, Stainless Steel, HSLA, Iron-Base Super alloys• L5xxxx - Lead Alloys, including Babbitt Alloys and Solder Alloys• M1xxxx - Magnesium Alloys• Nxxxxx - Nickel Alloys• Rxxxxx - Refractory Alloys
– R03xxx- Molybdenum Alloys– R04xxx- Niobium (Columbium) Alloys– R05xxx- Tantalum Alloys– R3xxxx- Cobalt Alloys– R5xxxx- Titanium Alloys– R6xxxx- Zirconium Alloys
• Sxxxxx - Stainless Steels, including Precipitation Hardening Stainless Steel and Iron-Based Superalloys
• Txxxxx - Tool Steels• Zxxxxx - Zinc Alloys
GXXXXX GRADE for carbon steel & alloy steel
• Carbon steel is defined as steel that have no minimum percentage of elements are normally considered alloying elements like (Mn, Si, Cr, Ni, and Cu).Carbon steel must have less than 1.65% Mn, 0.6% Si and 0.6%Cu.
• Alloy steel has manganese, silicon and copper more than above limits.
Classification of Carbon & Alloy steels
• They are classified to many types according to:• - Chemical composition as SAE (Society of
Automotive Engineer) • - Mechanical properties such as strength as in
ASTM (American Society for Testing and Materials)• - Manufacturing methods e.g. (BOF or EF)• - Finishing methods (hot rolling, cold rolling)• - The product shape (bar, sheet, etc)• - The microstructure (ferrite, martensit, austenitic)• - Heat treatment (annealed, normalized, quenched
and tempered)
CARBON&ALLOY STEEL TYPES IN UNS• Carbon and alloy steel in UNS take G letter and first four digits are SAE
designation, for example G10400, the (E) letter for electric furnace add in SAE;E52100c make in UNS number ‘’6’’ at fifth digit;G52986
• - CARBON STEEL FOR GENERAL USE• G10050, G10060, G10080, G10100, G10120• - Rephosphorized & Resulphurized carbon steel• G12110, G12120, G12130, G12134, G12144, G12150• - Carbon manganese steel• G15130, G15180, G15220, G15240, G15250, G15260, G15270, G15330,
G15340, G15360• Chromium – Molybdenum steel • G41180,G41200,G41210,G41300,G41370,G41400,G41420,G41450,G41
470,G41500,G41610• - Ni-Cr-Mo Steel• G43400, G87400
INTERNATIONAL MATERIAL GRADE COMPARISON TABLE
• When selection of materials from many sources dependent on countries that product, UNS put with same partition as USA standard with (AISI/SAE), when we compare one material between deferent designations may be saw one standard not found in partition; as example and we can see in tables of comparison:
• USA (AISI/SAE UNS) 1010• FRANCE (AFNOR) CC10• GERMANY (DIN) CK10• GREAT BRITAIN (BS) 040A10• ITALY (UNI) NOT FOUND• SWEDEN (SS) 1264• SPAIN (UNE) NOT FOUND • JAPAN (JIS) NOT FOUND
CONCLUSION• Knowledge of designation depends on many
essentials principles; chemical composition, mechanical properties, manufacturing process and others.
• UNS system depend on AISI and SAE ; take the partition that specialist for carbon and alloy steel ,my sources have tables and must understanding the items in it ,before that know of grades for carbon steel & alloy steels according to AISI/SAE as in attached files .
REFRENCES
• - ASME SECTION II 2000 Materials index 2nd edition published by CASTI
• - Handbook of Comparative World Steel Standards ASTM DS67A 2nd Edition
• John E. Bringas, Editor 2002• - ASTM E527-83 APROVED 2003• -Metals black book 5th edition 2003BlackBookNALite.pdf• - Engineering hand book G.L.HUYETT 2004• -Blue book CHEMICAL ANALYSES OF STANDARD SIZES 2007
attached• - MARYLAND METRICS Technical Data Chart
International Material Grade Comparison Table• Springer Handbook of Condensed Matter and materials Data
Springer Berlin Heidelberg 2005Printed in Germany