Unifit Metalloys Inc is known for making and exporting AISI 4140 fasteners also known as UNS G41400 that are built to handle tough jobs. These fasteners are made from chromium molybdenum alloy steel which means they’re strong, heat treatable, easy to machine and ready to last. We offer made to order AISI 4130 fasteners in varieties of bolts, screws, stud bolts, threaded rods, nuts, washers, pins & other bolting components, in hot forged condition, giving customers additional customized options for critical applications. They’re designed for high stress environments where strength, toughness and wear resistance really matter.
You’ll find these fasteners used across industries like aerospace automotive oil and gas petrochemical and heavy engineering. They’re built to perform even in harsh environments like those with boiling nitric acid between 50 to 65 percent thanks to their carefully controlled silicon and carbon levels. Our 4140 fasteners can also handle heat really well with resistance to scaling up to 1050°C. That makes them a solid choice for equipment like heat exchangers pumps, tanks, coolers and pipelines where strength and long term reliability really count.
Request QuoteAISI 4140 isn’t just another alloy steel - it’s the kind people reach for when strength really matters. It’s a mix of chromium and molybdenum which gives it that extra edge in toughness and wear resistance. Some know it as UNS G41400 but most just know it works. It machines pretty well holds up under stress and doesn’t quit when things get rough. That’s why you see it used everywhere in cars, planes, oil rigs and big industrial machines.
Now when you’re talking fasteners AISI 4140 really proves its worth. It can be heat treated to get the right level of hardness depending on what you need. And it doesn’t just handle pressure once - it keeps going through repeated loads without breaking down. Whether it’s bolts, nuts, washers or screws these fasteners don’t just fit in - they hold everything together when it matters most. Heat vibration pressure as they’re built for all of it.
At Unifit Fastener we make and supply a wide range of AISI 4140 fasteners built to handle some of the toughest jobs out there. These fasteners are designed for strength and wear resistance so they hold up well even in demanding industrial environments. Below you’ll find the different types of AISI 4140 fasteners we manufacture to meet your specific needs.
Whether you need standard components or custom-built 4140 fasteners, we ensure quality, precision and timely delivery to meet your specific application needs.
To really understand why AISI 4140 fasteners performs the way it does you’ve got to look at its chemical makeup. It’s the balance of elements that gives it that solid mix of strength, toughness and wear resistance.
| Material | Percentage (%) |
|---|---|
| Carbon (C) | 0.38 – 0.43 |
| Manganese (Mn) | 0.75 – 1.00 |
| Chromium (Cr) | 0.80 – 1.10 |
| Molybdenum (Mo) | 0.15 – 0.25 |
| Silicon (Si) | 0.15 – 0.35 |
| Sulfur (S) | ≤ 0.040 |
| Phosphorus (P) | ≤ 0.035 |
| Iron (Fe) | 96.785 – 97.77 |
The way these elements are balanced in AISI 4140 or SAE 4140 steel really boosts its performance when things get intense. That’s why fasteners made from it tend to last long and stay reliable even in industries where the situation is always demanding.
AISI 4140 is known around the world for its solid mix of strength, toughness and fatigue resistance. Since it’s used across so many industries and countries you’ll find it listed under different standards and material codes. That makes it easier to match and use globally especially when sourcing fasteners. Here are some of the most common AISI 4140 material equivalents used in fastener manufacturing:
| AISI | UNS | WERKSTOFF NR. |
|---|---|---|
| Grade 4140 | G41400 | 1.7225 |
AISI 4140 fasteners are produced as per international ASTM and ASME standards, ensuring high strength and reliability. They are available in multiple lengths, sizes, and custom dimensions to suit various industrial applications.
| Specification | Details |
|---|---|
| Specifications | ASTM A193 / ASME SA193 |
| Length | 3mm to 200mm |
| Size | 3/6″ to 2″, M3 – M56, Custom Sizes |
AISI 4130 fasteners offer a balanced combination of strength, toughness, and machinability. Their mechanical profile makes them suitable for high-pressure and high-temperature service conditions. Below are the key mechanical properties in both metric and imperial units:
| Property (AISI 4130) | Metric | Imperial |
|---|---|---|
| Tensile Strength, Ultimate | 560 MPa | 81,200 psi |
| Tensile Strength, Yield | 460 MPa | 66,700 psi |
| Modulus of Elasticity | 190–210 GPa | 27,557–30,458 ksi |
| Bulk Modulus (Steel) | 140 GPa | 20,300 ksi |
| Shear Modulus (Steel) | 80 GPa | 11,600 ksi |
| Poisson’s Ratio | 0.27–0.30 | 0.27–0.30 |
| Elongation at Break (50 mm) | 21.50% | 21.50% |
| Reduction of Area | 59.6% | 59.60% |
| Hardness, Brinell | 217 HB | 217 HB |
| Hardness, Knoop (Converted) | 240 | 240 |
| Hardness, Rockwell B (Converted) | 95 HRB | 95 HRB |
| Hardness, Rockwell C (Converted)* | 17 HRC | 17 HRC |
| Hardness, Vickers (Converted) | 228 HV | 228 HV |
| Machinability (Annealed/Cold Drawn, Based on AISI 1212 = 100%) | 70% | 70% |
These properties contribute directly to the fastener's ability to maintain integrity under pressure, making AISI 4140 a reliable choice for automotive, oil & gas and aerospace fastening systems.
AISI 4140 steel is one of those materials people count on when things get tough. It’s strong, dependable and built to take a beating which is why it’s a popular choice for fasteners used in demanding environments. Whether it’s heavy machinery, aerospace or oil and gas work these fasteners are made to hold up when it matters most.
Here’s what makes AISI 4140 fasteners stand out:
Because of all this AISI 4140 fasteners are trusted in places where failure just isn’t an option. If you need reliability under pressure these fasteners are the kind of hardware you want on the job.
People trust AISI 4140 fasteners because they’re strong and they don’t quit under pressure. You’ll find them in jobs where there’s no room for failure and the kind of work that needs parts to hold up day after day. They’ve got the toughness and performance to handle rough conditions and heavy use. That’s why they’re often used where fatigue resistance and long term durability really matter.
These fasteners show up in all kinds of industries like:
These fasteners are essential in ensuring high performance and reliability across a wide range of critical industries and applications.
Need AISI 4140 fasteners that actually meet top industry standards? You’re in the right place. We offer a wide selection of fasteners made to ASTM DIN & ISO specs and we keep our AISI 4140 prices in India fair and competitive. Whether you’re in automotive aerospace oil and gas or heavy engineering these fasteners are built to give you strength, durability and solid performance where it counts.
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Request QuoteAISI 4130 is a low-alloy chromium–molybdenum steel known for its high strength, good toughness, and excellent weldability. It can be heat treated to enhance hardness and wear resistance, making it suitable for fasteners, pressure vessels, aircraft parts, oil & gas equipment, and heavy engineering components.
AISI 4130 has various international equivalents including UNS G41300, EN 1.7218, 42CrMo4, BS 970 708M40, and JIS SCM430. These grades offer similar chemical composition and mechanical properties, making them interchangeable in most industrial applications.
Yes. AISI 4140 can be quenched and tempered to achieve higher tensile strength, hardness, and wear resistance, making it suitable for high-stress equipment and heavy-duty bolting applications.
They can withstand elevated temperatures, with resistance to scaling around 1050°C, depending on service conditions and protective coatings.