FE-18NI-9CO-5MO-0.6TI-0.1AL VIM+ESR ROUND BAR MANUFACTURING: ADVANCED MARAGING 300 STEEL FOR AEROSPACE, DEFENSE AND HIGH-STRENGTH ENGINEERING FE-18NI-9CO-5MO-0.6TI-0.1AL VIM+ESR ROUND BAR MANUFACTURING IS ASSOCIATED WITH THE HIGH-STRENGTH 18NI MARAGING 300 / MARAGING C300 CLASS OF PRECIPITATION-HARDENING STEELS. THIS ALLOY FAMILY IS WIDELY RECOGNIZED FOR ITS EXCEPTIONAL STRENGTH-TO-WEIGHT CAPABILITY, HIGH FRACTURE TOUGHNESS, GOOD DIMENSIONAL STABILITY DURING AGING, EXCELLENT MACHINABILITY IN THE SOLUTION-TREATED CONDITION, AND STRONG PERFORMANCE IN DEMANDING AEROSPACE, DEFENSE, TOOLING AND HIGH-PERFORMANCE ENGINEERING APPLICATIONS. COMMON INTERNATIONAL IDENTIFIERS INCLUDE MARAGING 300, MARAGING C300, 18NI(300), UNS K93120, AMS 6514 AND WERKSTOFF 1.6358 / X2NICOMO18-9-5. WHAT IS FE-18NI-9CO-5MO-0.6TI-0.1AL MARAGING STEEL? FE-18NI-9CO-5MO-0.6TI-0.1AL IS A LOW-CARBON, NICKEL-COBALT-MOLYBDENUM MARAGING STEEL CHEMISTRY BELONGING TO THE CONVENTIONAL 18NI(300) STRENGTH CLASS. MARAGING STEELS ACHIEVE THEIR PROPERTIES DIFFERENTLY FROM CONVENTIONAL QUENCHED-AND-TEMPERED ALLOY STEELS: A RELATIVELY SOFT, TOUGH MARTENSITIC MATRIX IS PRODUCED FIRST, FOLLOWED BY CONTROLLED PRECIPITATION HARDENING DURING AGING. FOR THE MARAGING 300 FAMILY, NICKEL IS TYPICALLY AROUND 18–19%, COBALT IS APPROXIMATELY 8–9.5%, MOLYBDENUM IS ABOUT 4.6–5.2%, TITANIUM IS ROUGHLY 0.55–0.80%, AND ALUMINUM IS GENERALLY CONTROLLED AT LOW LEVELS. THE BALANCE IS IRON, WITH VERY LOW CARBON AND TIGHTLY CONTROLLED RESIDUAL AND IMPURITY ELEMENTS. THE STATED 9% CO AND 0.6% TI COMPOSITION IS THEREFORE STRONGLY ALIGNED WITH THE MARAGING 300 / C300 FAMILY RATHER THAN MARAGING 250. MARAGING 300 IS THE HIGHER-STRENGTH CONVENTIONAL 18NI GRADE AND IS COMMONLY IDENTIFIED WITH UNS K93120 AND AMS 6514. INTERNATIONAL EQUIVALENTS, COMMON NAMES AND DESIGNATIONS THE MOST IMPORTANT INTERNATIONAL AND COMMERCIAL DESIGNATIONS ASSOCIATED WITH THIS MATERIAL INCLUDE: MARAGING 300 MARAGING STEEL 300 MARAGING C300 C300 MARAGING STEEL 18NI(300) 18NI MARAGING 300 18NI-9CO-5MO MARAGING STEEL UNS K93120 AMS 6514 ASTM A579 REFERENCES USED FOR HIGH-STRENGTH ALLOY-STEEL FORMS MIL-S-46850 MARAGING-STEEL CLASSIFICATION REFERENCES WERKSTOFF NO. 1.6358 X2NICOMO18-9-5 TECHNICAL AND COMMERCIAL SOURCES ALSO ASSOCIATE THE MATERIAL WITH PROPRIETARY OR HISTORICAL NAMES SUCH AS VASCOMAX C300, VDIMOR 300, UDIMAR 300, AND OTHER PRODUCER-SPECIFIC MARAGING-STEEL TRADE NAMES. TRADEMARK DESIGNATIONS SHOULD NOT BE TREATED AUTOMATICALLY AS IDENTICAL SPECIFICATIONS; THE GOVERNING CHEMISTRY, PRODUCT FORM, HEAT TREATMENT AND CERTIFICATION REQUIREMENTS SHOULD ALWAYS BE CHECKED. SOME EUROPEAN DATABASES AND SUPPLIERS REFERENCE 1.6358 AND X2NICOMO18-9-5 FOR THE MARAGING 300 FAMILY. BECAUSE NATIONAL STANDARDS AND HISTORICAL SPECIFICATIONS CAN OVERLAP OR EVOLVE, THE MATERIAL CERTIFICATE AND APPLICABLE REVISION OF THE PURCHASING SPECIFICATION REMAIN DECISIVE. MAJOR SPECIFICATION STANDARDS FOR MARAGING 300 ROUND BAR FOR ROUND BAR AND FORGING STOCK, SAE AMS 6514 IS ONE OF THE KEY AEROSPACE SPECIFICATIONS ASSOCIATED WITH MARAGING 300. UNS K93120 IS THE CORRESPONDING WIDELY USED UNIFIED NUMBERING SYSTEM IDENTIFICATION. FREQUENTLY ENCOUNTERED STANDARDS AND REFERENCES INCLUDE: • AMS 6514 – MARAGING 300 BAR AND FORGING STOCK • UNS K93120 – MARAGING 300 • MIL-S-46850 – MARAGING STEEL MILITARY SPECIFICATION FAMILY • ASTM A579 – SPECIFICATION FOR SUPERSTRENGTH ALLOY STEEL FORGINGS • WERKSTOFF 1.6358 • X2NICOMO18-9-5 • SELECTED HISTORICAL OR CUSTOMER-SPECIFIC AEROSPACE AND DEFENSE MATERIAL SPECIFICATIONS MAY ALSO BE SPECIFIED ACCORDING TO CONTRACT, DRAWING OR PROCUREMENT SYSTEM. A MANUFACTURER SHOULD NOT STATE THAT EVERY ONE OF THESE STANDARDS IS AUTOMATICALLY INTERCHANGEABLE. A TECHNICALLY CORRECT PURCHASE DESCRIPTION SHOULD SPECIFY THE EXACT GRADE, PRODUCT FORM, APPLICABLE STANDARD AND REVISION, MELTING ROUTE, HEAT-TREATMENT CONDITION, DIMENSIONS, TESTING REQUIREMENTS AND CERTIFICATION REQUIREMENTS. VIM + ESR MANUFACTURING OF MARAGING 300 ROUND BAR THE PHRASE VIM + ESR INDICATES A PREMIUM MELTING AND REFINING ROUTE INTENDED TO PROVIDE HIGH METALLURGICAL CLEANLINESS AND CONSISTENCY. VACUUM INDUCTION MELTING (VIM) IS TYPICALLY USED TO PRODUCE THE INITIAL CONTROLLED-ALLOY HEAT. VACUUM MELTING HELPS MANAGE GASES AND PERMITS CLOSE CONTROL OF THE NICKEL, COBALT, MOLYBDENUM, TITANIUM AND ALUMINUM ADDITIONS REQUIRED BY THE MARAGING-STEEL CHEMISTRY. AFTER VIM, ELECTROSLAG REMELTING (ESR) CAN BE EMPLOYED TO FURTHER REFINE THE INGOT AND IMPROVE INTERNAL SOUNDNESS, CLEANLINESS AND CHEMICAL UNIFORMITY. FOR DEMANDING APPLICATIONS, ESR IS VALUABLE FOR REDUCING UNDESIRABLE INCLUSIONS AND IMPROVING CONSISTENCY THROUGH THE SUBSEQUENT FORGING AND BAR-MAKING OPERATIONS. A TYPICAL VIM+ESR PRODUCTION ROUTE CAN INCLUDE: RAW MATERIAL SELECTION → VIM MELTING → ESR REMELTING → HOMOGENIZATION → BREAKDOWN FORGING → HOT FORGING/ROLLING → SOLUTION TREATMENT → CONTROLLED COOLING → STRAIGHTENING → MACHINING OR PEELING → ULTRASONIC AND SURFACE INSPECTION → DIMENSIONAL INSPECTION → FINAL CERTIFICATION THE ACTUAL ROUTE VARIES ACCORDING TO THE PRODUCER'S EQUIPMENT, PRODUCT DIAMETER, SPECIFICATION AND CUSTOMER REQUIREMENTS. ROUND BAR FORGING AND HOT WORKING AFTER ESR, THE INGOT IS CONVERTED INTO WORKABLE BILLET OR BAR STOCK THROUGH CONTROLLED HOT DEFORMATION. FORGING REDUCTION IS IMPORTANT BECAUSE IT PROMOTES A REFINED, UNIFORM WROUGHT STRUCTURE AND HELPS REDUCE THE EFFECTS OF THE ORIGINAL CAST STRUCTURE. THE MANUFACTURER MUST CONTROL: • FORGING TEMPERATURE • REDUCTION RATIO • INTERMEDIATE REHEATING • SURFACE CONDITION • GRAIN REFINEMENT • CENTER SOUNDNESS • FINAL DIMENSIONAL TOLERANCES • COOLING RATE AFTER HOT WORKING LARGE-DIAMETER MARAGING 300 ROUND BARS MAY REQUIRE MULTIPLE FORGING STAGES TO ACHIEVE THE REQUIRED METALLURGICAL QUALITY THROUGHOUT THE CROSS SECTION. SOLUTION ANNEALING OF MARAGING 300 ROUND BAR UNLIKE CONVENTIONAL ALLOY STEELS THAT DEPEND ON A QUENCH TRANSFORMATION FOR THEIR FINAL HIGH STRENGTH, MARAGING 300 RELIES ON A CONTROLLED PRECIPITATION-HARDENING SEQUENCE. THE SOLUTION-TREATMENT STAGE CREATES THE APPROPRIATE LOW-CARBON MARTENSITIC MATRIX AFTER COOLING. PUBLISHED TECHNICAL DATA FOR MARAGING 300 COMMONLY IDENTIFY SOLUTION TREATMENT AROUND THE 800°C CLASS, FOLLOWED BY CONTROLLED COOLING, ALTHOUGH THE PRECISE TEMPERATURE AND HOLDING TIME MUST BE TAKEN FROM THE GOVERNING MATERIAL SPECIFICATION AND PRODUCT SIZE. THE SOLUTION-TREATED CONDITION PROVIDES RELATIVELY HIGH TOUGHNESS AND EXCELLENT MACHINABILITY COMPARED WITH THE FULLY AGED CONDITION. AGING AND PRECIPITATION HARDENING THE DEFINING PRODUCTION STEP IS AGING HEAT TREATMENT. DURING AGING, INTERMETALLIC PRECIPITATES FORM WITHIN THE NICKEL-RICH MARTENSITIC MATRIX. THESE PRECIPITATES DRAMATICALLY INCREASE YIELD STRENGTH, TENSILE STRENGTH AND HARDNESS WITHOUT THE SEVERE DISTORTION COMMONLY ASSOCIATED WITH CONVENTIONAL HARDENING-AND-QUENCHING SYSTEMS. MARAGING 300 IS COMMONLY ASSOCIATED WITH AGING IN THE VICINITY OF 480°C / 900°F, WITH EXACT TIME AND TEMPERATURE DEPENDING ON THE SPECIFICATION AND REQUIRED CONDITION. COMMERCIAL TECHNICAL DATA REPORT TENSILE STRENGTHS AROUND THE 290 KSI CLASS AFTER TYPICAL AGING TREATMENTS, WHILE OTHER SOURCES REPORT APPROXIMATELY 1, 900–2, 050 MPA DEPENDING ON PROCESSING AND CONDITION. BECAUSE ACTUAL PROPERTIES DEPEND ON DIAMETER, PRIOR THERMAL HISTORY, ORIENTATION AND HEAT TREATMENT, CERTIFIED MECHANICAL-TEST RESULTS SHOULD ALWAYS BE USED FOR FINAL ACCEPTANCE. MACHINING OF VIM+ESR MARAGING 300 ROUND BAR ONE MAJOR ADVANTAGE OF MARAGING 300 IS ITS MACHINABILITY IN THE SOLUTION-TREATED CONDITION. LOW CARBON CONTENT MAKES THE MATERIAL SUBSTANTIALLY EASIER TO MACHINE BEFORE AGING THAN MANY ULTRA-HIGH-STRENGTH QUENCHED-AND-TEMPERED STEELS. COMPLEX SHAFTS, LANDING-GEAR PARTS, TOOLING COMPONENTS, HIGH-STRENGTH FASTENERS AND PRECISION AEROSPACE PARTS CAN THEREFORE BE MACHINED CLOSE TO FINAL DIMENSIONS BEFORE THE FINAL PRECIPITATION-AGING STEP. MANUFACTURERS COMMONLY SUPPLY BAR AS: BRIGHT ROUND BAR, PEELED ROUND BAR, FORGED ROUND BAR, GROUND ROUND BAR, PRECISION-MACHINED BAR AND CUT-TO-LENGTH ROUND BAR. FINAL DIMENSIONAL AND SURFACE REQUIREMENTS SHOULD BE DEFINED SEPARATELY FROM THE METALLURGICAL SPECIFICATION. QUALITY CONTROL IN MARAGING 300 ROUND BAR MANUFACTURING HIGH-QUALITY VIM+ESR MARAGING 300 ROUND BAR MANUFACTURING REQUIRES MUCH MORE THAN CHEMICAL ANALYSIS ALONE. TYPICAL QUALITY-CONTROL STAGES CAN INCLUDE POSITIVE MATERIAL IDENTIFICATION, HEAT ANALYSIS, PRODUCT CHEMICAL ANALYSIS, TENSILE TESTING, HARDNESS TESTING, METALLOGRAPHIC EXAMINATION, DIMENSIONAL INSPECTION AND NON-DESTRUCTIVE TESTING. FOR CRITICAL AEROSPACE AND DEFENSE APPLICATIONS, ULTRASONIC EXAMINATION IS PARTICULARLY IMPORTANT FOR DETECTING INTERNAL DISCONTINUITIES. DEPENDING ON THE PURCHASE ORDER, ULTRASONIC INSPECTION CAN BE SUPPLEMENTED BY MAGNETIC-PARTICLE OR LIQUID-PENETRANT INSPECTION FOR SURFACE-BREAKING DEFECTS. DOCUMENTATION CAN INCLUDE: MILL TEST CERTIFICATE (MTC) EN 10204 3.1 OR 3.2 CERTIFICATION WHERE CONTRACTUALLY APPLICABLE HEAT-TREATMENT CHARTS MECHANICAL TEST REPORTS CHEMICAL ANALYSIS ULTRASONIC TEST REPORT DIMENSIONAL INSPECTION REPORT TRACEABILITY DOCUMENTATION THE EXACT INSPECTION PLAN SHOULD BE MATCHED TO THE GOVERNING AMS, ASTM, MILITARY, CUSTOMER OR AEROSPACE SPECIFICATION. MECHANICAL PROPERTIES OF MARAGING 300 THE ATTRACTION OF MARAGING 300 IS ITS COMBINATION OF EXTREMELY HIGH STRENGTH WITH USEFUL FRACTURE TOUGHNESS AND DUCTILITY. PUBLISHED TECHNICAL DATA FOR MARAGING 300 SHOW THAT, AFTER APPROPRIATE AGING, THE MATERIAL CAN REACH APPROXIMATELY 280–290 KSI TENSILE-STRENGTH TERRITORY, WITH YIELD STRENGTH AROUND THE 250–280 KSI CLASS, DEPENDING ON THE SPECIFICATION, HEAT TREATMENT AND PRODUCT CONDITION. HARDNESS CAN REACH APPROXIMATELY THE LOW-50S HRC AFTER AGING. THE ALLOY ALSO OFFERS GOOD RESISTANCE TO CRACK PROPAGATION AND EXCELLENT NOTCH DUCTILITY, MAKING IT PARTICULARLY USEFUL WHERE CONVENTIONAL HIGH-CARBON ULTRA-HIGH-STRENGTH STEELS MAY PRESENT UNACCEPTABLE TOUGHNESS OR DISTORTION CHARACTERISTICS. APPLICATIONS OF MARAGING 300 ROUND BAR FE-18NI-9CO-5MO-0.6TI-0.1AL / MARAGING 300 ROUND BAR IS SUITED TO APPLICATIONS REQUIRING VERY HIGH STRENGTH, TOUGHNESS, DIMENSIONAL STABILITY AND RELIABLE FATIGUE PERFORMANCE. TYPICAL APPLICATIONS INCLUDE: AEROSPACE LANDING-GEAR COMPONENTS AIRCRAFT STRUCTURAL COMPONENTS ROCKET AND MISSILE HARDWARE ROCKET MOTOR CASES ACTUATOR COMPONENTS HIGH-STRENGTH SHAFTS GEARS HIGH-PERFORMANCE FASTENERS TOOLING AND DIES EXTRUSION TOOLING MACHINE-TOOL COMPONENTS HIGH-STRENGTH SPRINGS AND PRECISION ENGINEERING PARTS MARAGING 300 IS ALSO USED IN DEMANDING DEFENSE AND HIGH-PERFORMANCE INDUSTRIAL APPLICATIONS WHERE STRENGTH AND DIMENSIONAL STABILITY ARE MAJOR DESIGN REQUIREMENTS. WHY CHOOSE VIM + ESR FOR MARAGING 300 ROUND BAR? THE COMBINATION OF VIM AND ESR IS PARTICULARLY ATTRACTIVE WHEN CUSTOMERS REQUIRE CONSISTENT CHEMISTRY, HIGH CLEANLINESS AND DEPENDABLE INTERNAL QUALITY. VIM SUPPORTS PRECISE CONTROL OF ALLOYING ADDITIONS, WHILE ESR PROVIDES ADDITIONAL REFINING AND SOLIDIFICATION CONTROL. THIS MAKES THE PROCESS ATTRACTIVE FOR HIGH-INTEGRITY ROUND BAR INTENDED FOR CRITICAL AEROSPACE AND DEFENSE APPLICATIONS. FOR DEMANDING COMPONENTS, BUYERS MAY ADDITIONALLY REQUIRE CONTROLLED GRAIN STRUCTURE, UT ACCEPTANCE CRITERIA, MINIMUM FORGING REDUCTION, INCLUSION LIMITS, TRACEABILITY AND COMPLETE HEAT-TREATMENT RECORDS. FE-18NI-9CO-5MO-0.6TI-0.1AL INDUSTRY SEARCH KEYWORDS FOR INTERNATIONAL VISIBILITY, HIGH-DEMAND TERMINOLOGY SHOULD COMBINE THE ALLOY NAME WITH PRODUCT FORM, MANUFACTURING PROCESS, SPECIFICATION AND APPLICATION TERMINOLOGY. IMPORTANT HIGH-VALUE SEARCH PHRASES INCLUDE: MARAGING 300 ROUND BAR MARAGING STEEL ROUND BAR MARAGING 300 STEEL BAR MARAGING C300 ROUND BAR MARAGING 300 BAR 18NI MARAGING STEEL 18NI(300) MARAGING STEEL 18NI MARAGING 300 UNS K93120 ROUND BAR UNS K93120 STEEL AMS 6514 ROUND BAR AMS 6514 BAR MARAGING 300 AMS 6514 1.6358 ROUND BAR 1.6358 MARAGING STEEL X2NICOMO18-9-5 ROUND BAR MARAGING 300 FORGED BAR MARAGING STEEL FORGED ROUND BAR VIM ESR MARAGING STEEL VIM+ESR ROUND BAR VACUUM MELTED MARAGING STEEL AEROSPACE MARAGING STEEL HIGH STRENGTH MARAGING STEEL ULTRA HIGH STRENGTH STEEL ROUND BAR AEROSPACE ROUND BAR MANUFACTURER MARAGING STEEL MANUFACTURER MARAGING STEEL SUPPLIER MARAGING 300 STOCKIST MARAGING 300 EXPORTER MARAGING STEEL ROUND BAR SUPPLIER THESE KEYWORD CLUSTERS ARE DESIGNED AROUND COMMON GLOBAL PRODUCT, GRADE, STANDARDS, PROCESS AND PROCUREMENT TERMINOLOGY. EXACT MONTHLY SEARCH-VOLUME FIGURES VARY BY COUNTRY, SEARCH ENGINE, LANGUAGE AND COMMERCIAL KEYWORD DATABASE, SO IT WOULD BE MISLEADING TO CLAIM A PRECISE WORLDWIDE NUMERICAL RANKING WITHOUT ACCESS TO A PROPRIETARY GLOBAL KEYWORD-VOLUME DATASET. MARAGING 300 ROUND BAR MANUFACTURING FOR GLOBAL EXPORT FOR INTERNATIONAL BUYERS, A PROFESSIONAL MANUFACTURING SPECIFICATION SHOULD CLEARLY IDENTIFY THE MATERIAL AS, FOR EXAMPLE: MARAGING 300 / C300 / UNS K93120 / 1.6358 / X2NICOMO18-9-5, VIM + ESR, FORGED ROUND BAR, SOLUTION ANNEALED OR AGED CONDITION, TO THE APPLICABLE AMS SPECIFICATION. THE PURCHASE DOCUMENTATION SHOULD ALSO DEFINE DIAMETER, LENGTH, STRAIGHTNESS, SURFACE FINISH, MACHINING ALLOWANCE, ULTRASONIC TESTING, MECHANICAL-PROPERTY REQUIREMENTS, HEAT-TREATMENT CONDITION AND CERTIFICATION LEVEL. THIS APPROACH AVOIDS CONFUSION BETWEEN MARAGING 250, MARAGING 300 AND MARAGING 350, WHICH HAVE DIFFERENT COBALT, MOLYBDENUM AND TITANIUM LEVELS AND CONSEQUENTLY DIFFERENT PERFORMANCE CHARACTERISTICS. CONCLUSION FE-18NI-9CO-5MO-0.6TI-0.1AL VIM+ESR ROUND BAR MANUFACTURING BELONGS TO THE GLOBALLY IMPORTANT MARAGING 300 / MARAGING C300 / 18NI(300) FAMILY OF ULTRA-HIGH-STRENGTH PRECIPITATION-HARDENING STEELS. THE PRINCIPAL INTERNATIONAL IDENTIFIERS INCLUDE UNS K93120, AMS 6514, 1.6358 AND X2NICOMO18-9-5, WHILE COMMERCIAL REFERENCES INCLUDE C300, MARAGING 300, UDIMAR 300, VDIMOR 300 AND VASCOMAX C300, SUBJECT TO MANUFACTURER-SPECIFIC DESIGNATION AND SPECIFICATION VERIFICATION. A PROPERLY CONTROLLED VIM + ESR MELTING ROUTE, FOLLOWED BY OPTIMIZED FORGING, SOLUTION TREATMENT, PRECISION MACHINING AND PRECIPITATION AGING, CAN PRODUCE HIGH-INTEGRITY MARAGING 300 ROUND BAR FOR AEROSPACE, DEFENSE, TOOLING AND OTHER ULTRA-HIGH-STRENGTH ENGINEERING APPLICATIONS. THE FINAL PROCUREMENT SPECIFICATION SHOULD ALWAYS IDENTIFY THE EXACT GOVERNING STANDARD AND REVISION RATHER THAN ASSUMING ALL LISTED EQUIVALENTS ARE AUTOMATICALLY INTERCHANGEABLE.