GB/T 3077 Compliant Forgings — Chinese National Standard Alloy Structural Steel Grades, the Alloy Counterpart to GB/T 699 Carbon Steel
Shivam Forge manufactures alloy structural steel forgings to GB/T 3077 — the Chinese national standard covering alloy grades including 40Cr, 42CrMo, and 20CrMnTi — for customers whose drawings specify Chinese-standard alloy steel and who are qualifying an alternative manufacturing base without redrawing to a different national standard. Rajkot, India. Call +91-9265772827.
GB/T 3077 is the direct alloy-steel counterpart to GB/T 699, the Chinese national carbon structural steel standard the site separately covers, and the relationship between the two mirrors a distinction familiar across every national steel standard system: GB/T 699 grades derive their properties from carbon content and heat treatment alone, while GB/T 3077 grades add chromium, molybdenum, manganese, titanium, and other alloying elements specifically to increase hardenability, elevate strength, and in some grades improve elevated-temperature or wear performance beyond what plain carbon chemistry can deliver. Within GB/T 3077's grade range, three families see particularly wide use and map onto familiar roles from other national standards: 40Cr, a through-hardening chromium alloy steel broadly comparable in role to SAE 5140, used for shafts and structural components needing more hardenability than plain carbon grade 45 steel (from GB/T 699) provides; 42CrMo, a chromium-molybdenum grade functionally comparable to SAE 4140 or JIS SCM440, used for higher-strength shafts, gears, and structural components; and 20CrMnTi, a case-hardening chromium-manganese-titanium alloy extremely widely specified across Chinese automotive gear manufacturing, filling a role broadly comparable to SAE 8620 or JIS SCM420 as a carburizing grade combining good hardenability with core toughness. As with GB/T 699, the practical value of manufacturing directly to GB/T 3077's specific composition and property requirements — rather than substituting an approximated JIS, DIN, or SAE equivalent — is that it lets a component drawing already written against Chinese-standard alloy steel move to an alternative supply base without triggering a redesign or standard-conversion cycle.
Forged shaft and structural component blanks in GB/T 3077 grade 40Cr, a chromium through-hardening alloy steel offering meaningfully better hardenability than plain carbon grade 45 steel for applications with heavier cross-sections or higher strength requirements.
Forged gear blank and shaft components in 42CrMo, a chromium-molybdenum alloy steel functionally comparable to SAE 4140 and JIS SCM440, specified for the balanced strength-toughness profile this alloy family delivers across global machinery manufacturing.
Forged gear blank components in 20CrMnTi, the case-hardening chromium-manganese-titanium grade extremely widely specified across Chinese automotive and machinery gear manufacturing for carburized, wear-resistant gear tooth applications.
Forged components manufactured directly to the GB/T 3077 grade already specified on an existing drawing, supporting customers qualifying an alternative supply base without a standard-conversion or redesign cycle.
Melt chemistry controlled to GB/T 3077's specific alloying element composition requirements for the ordered grade, including the residual element tolerance bands that distinguish the standard from superficially similar JIS, DIN, or SAE equivalents.
Heat treatment matched to the specific grade and application — quench and temper for through-hardening grades like 40Cr and 42CrMo, or carburizing and case hardening for grades like 20CrMnTi — per GB/T 3077's designated condition and property requirements.
Tensile, yield, elongation, hardness, and case depth testing (where applicable) performed and reported against GB/T 3077's specific requirements for the ordered grade, verifying the forging meets the standard rather than an approximate equivalent.
Material test certificates per EN 10204 3.1/3.2 documenting GB/T 3077 compliance, with cross-reference guidance to comparable JIS, DIN, or SAE grades available where a customer's internal engineering team needs that mapping for reference.
Alloy structural steel standards exist across every major manufacturing tradition for the same underlying reason: plain carbon steel's hardenability and strength ceiling, however useful for a broad range of general components, isn't sufficient for shafts, gears, and structural parts that need deeper through-hardening, higher strength, or a reliably carburizable case for wear resistance. GB/T 3077 fills exactly this role within the Chinese national standard system, sitting directly alongside GB/T 699's plain carbon coverage the way SAE's alloy steel series sits alongside its carbon steel series, or JIS's SCM series sits alongside its S-C series — a parallel, alloyed grade family addressing the applications plain carbon chemistry can't adequately serve.
The specific grades within GB/T 3077 that see the widest practical use map fairly directly onto familiar roles from other national standards, which helps engineers unfamiliar with the Chinese system orient quickly: 40Cr functions similarly to SAE 5140 as a moderately alloyed through-hardening grade, 42CrMo occupies the same functional space as SAE 4140, DIN 42CrMo4, and JIS SCM440 as a chromium-molybdenum grade balancing strength and toughness, and 20CrMnTi fills the case-hardening role comparable to SAE 8620 or JIS SCM420, particularly dominant in Chinese automotive gear manufacturing specifically. Recognizing these functional parallels is useful for engineering cross-reference purposes, but it doesn't substitute for manufacturing and certifying to GB/T 3077's own specific composition and property requirements when a drawing or incoming inspection process explicitly calls out the Chinese standard.
This distinction matters most directly in the same supply-base-diversification context that drives much of the practical demand for GB/T 3077 manufacturing capability outside China: a component originally drawn and qualified against a GB/T 3077 grade can move to an alternative manufacturing base while the drawing, incoming inspection criteria, and downstream qualification documentation remain unchanged, provided the alternative supplier can actually forge and certify to the standard's real requirements rather than an approximated cross-reference grade. For procurement and engineering teams under pressure to diversify sourcing without absorbing a redesign cycle, that capability removes what would otherwise be a significant barrier to qualifying a new supplier.
For manufacturers and procurement teams sourcing alloy structural steel forgings to GB/T 3077 as part of a supply base diversification effort, Shivam Forge manufactures and certifies directly to the standard's specific composition, heat treatment, and mechanical property requirements across 40Cr, 42CrMo, 20CrMnTi, and related grades. Contact our engineering team at +91-9265772827 or sales@shivamforge.com with your drawing and grade requirement for a manufacturability review and quotation.
GB/T 699 covers Chinese plain carbon structural steel grades, where properties come from carbon content and heat treatment alone. GB/T 3077 is the alloy steel counterpart, covering grades with chromium, molybdenum, manganese-titanium, and other alloying additions specifically included to raise hardenability and strength beyond what plain carbon chemistry can deliver — the same relationship that exists between plain carbon and alloy steel standards in other national systems.
20CrMnTi is a case-hardening chromium-manganese-titanium alloy steel extremely widely specified in Chinese automotive and machinery gear manufacturing, filling a role broadly comparable to SAE 8620 or JIS SCM420 — carburized to develop a wear-resistant gear tooth surface over a tough core.
42CrMo and SAE 4140 (and JIS SCM440, DIN 42CrMo4) represent the same fundamental chromium-molybdenum alloy steel chemistry family and are generally treated as functionally comparable. Specific composition tolerance bands differ between the standards, which we verify against your exact drawing requirement to confirm compliance with whichever standard is actually specified.
Yes. We can forge directly to the GB/T 3077 grade specified on your existing drawing without requiring conversion to JIS, DIN, or SAE equivalents, supporting supply base diversification without a redesign or standard-conversion cycle.
Material test certificates per EN 10204 3.1 as standard, with 3.2 third-party witnessed certification available, documenting chemical composition and mechanical property compliance with the specific GB/T 3077 grade and condition your drawing specifies.
Why Choose Shivam Forge
Shivam Forge delivers precision hot-forged components from our integrated Shapar, Rajkot facility — covering forging, CNC machining, heat treatment, and quality inspection under one roof.
