An Overview of Stainless Steel Welding Rod E7018: Standards, Grades, and Mechanical Performance

Types of Stainless Steel Welding Rods: Understanding E7018 and Common Alternatives

A welding rod is a critical consumable in arc welding, responsible for forming the weld pool and providing filler metal. While the E7018 is one of the most widely used low-hydrogen electrodes, it's important to note that E7018 is not a stainless steel welding rod—it is designed for welding carbon and high-strength low-alloy steels. True stainless steel welding rods have designations such as E308, E309, or E316. However, the E7018 and similar carbon steel electrodes are often used in structural and industrial applications where strength, crack resistance, and high-quality welds are essential.

The following are some of the most common types of structural welding rods, including E7018 and other popular electrodes used in professional and hobbyist welding:

E7016

A low-hydrogen, iron powder electrode designed for AC/DC welding with excellent mechanical properties.

Advantages

• Excellent tensile strength (70,000 psi minimum)
• Good impact resistance at low temperatures
• Stable arc with medium penetration
• Suitable for all positions with proper technique

Limitations

• Requires proper storage to prevent moisture absorption
• Less forgiving on dirty or rusty surfaces
• Must be used with AC or specific DC polarity

Best for: Structural steel, pressure vessels, and environments requiring high weld integrity

E7018

A low-hydrogen, iron powder electrode known for producing high-strength, crack-resistant welds in critical applications.

Advantages

• Superior weld toughness and ductility
• Excellent for high-stress joints (e.g., bridges, buildings)
• Smooth arc and easy slag removal
• High deposition rate due to iron powder in flux

Limitations

• Sensitive to moisture—must be kept dry and baked if exposed
• Higher cost compared to cellulose electrodes
• Not ideal for dirty or contaminated surfaces

Best for: Critical structural welding, heavy fabrication, and applications requiring high impact resistance

E6010

A high-cellulose sodium electrode designed for deep penetration using DC+ polarity.

Advantages

• Deep penetration ideal for root passes
• Excellent on rusty, painted, or dirty metals
• Forceful arc ideal for out-of-position welding
• Minimal slag, easy cleanup

Limitations

• Only compatible with DC power sources
• Higher spatter compared to other rods
• Requires skilled technique for smooth finish

Best for: Pipeline welding, shipbuilding, and repair work on unclean surfaces

E6011

A versatile electrode with cellulose coating that works on both AC and DC currents.

Advantages

• Works on AC and DC power sources
• Good penetration on contaminated metals
• Flexible for all welding positions
• Great for field repairs and maintenance

Limitations

• Moderate deposition rate
• More spatter than E7018
• Weld appearance may be rougher

Best for: General repairs, farm equipment, and situations with limited power options

E6012

A medium-carbon electrode with a rutile-silica coating, offering a balance of usability and performance.

Advantages

• Smooth arc with low spatter
• Good for light to medium penetration
• Easy to use for beginners
• Reusable even after brief exposure to moisture

Limitations

• Shallow penetration compared to E6010/E6011
• Not ideal for deep groove welds
• Lower tensile strength than E7018

Best for: Light fabrication, sheet metal, and hobbyist welding projects

Expert Tip: Always store low-hydrogen electrodes like E7018 and E7016 in a heated quiver or rod oven (120–150°C) to prevent moisture absorption, which can lead to hydrogen-induced cracking in welds.

Clarification: True stainless steel welding rods (e.g., E308L-16, E309-15) are specifically formulated for welding stainless steels and offer corrosion resistance and thermal stability. The E7018, while excellent for structural steel, should not be used for stainless steel welding due to incompatible metallurgy.

Industry Applications of Stainless Steel Welding Rod E7018

E7018 welding rods are among the most widely used low-hydrogen, shielded metal arc welding (SMAW) electrodes in industrial applications. Known for their high tensile strength (70,000 psi), excellent crack resistance, and superior weld metal toughness, these rods are ideal for critical structural welds. Their low hydrogen content significantly reduces the risk of hydrogen-induced cracking—especially important in high-strength steels and thick-section welding.

While often referred to as “stainless steel” in casual conversation, E7018 rods are typically used for carbon and high-strength low-alloy steels rather than true stainless steels (which use specialized electrodes like E308L or E309L). However, their durability, strong deposition characteristics, and smooth arc performance make them indispensable across a range of demanding industries.

Key Industries Utilizing E7018 Welding Rods

Automotive Industry

In the automotive sector, E7018 rods are primarily used in the repair and reinforcement of heavy-duty vehicles and commercial fleets. Their ability to produce strong, ductile welds makes them ideal for critical safety components such as suspension systems, chassis frames, and braking system mounts.

These rods are especially valuable during frame straightening and collision repairs where structural integrity must be restored to factory specifications. The low-hydrogen nature of E7018 minimizes the risk of weld cracking in high-stress zones, ensuring long-term reliability under dynamic loading conditions.

Aerospace Industry

While full-scale aerospace manufacturing often employs advanced welding techniques like TIG or laser welding, E7018 rods play a crucial role in ground support equipment, maintenance hangars, and repair operations involving high-strength steel components.

They are frequently used in the fabrication and repair of landing gear housings, engine mounts, and structural support frames where weld integrity is non-negotiable. The precision, minimal spatter, and excellent bead appearance of properly applied E7018 welds contribute to consistent quality and compliance with stringent safety standards.

Construction Industry

The construction industry relies heavily on E7018 rods for welding structural steel components such as I-beams, girders, columns, and pressure vessels. These applications demand welds that can endure heavy loads, seismic stress, and environmental exposure.

E7018 electrodes provide the necessary combination of strength, toughness, and fatigue resistance required in high-rise buildings, bridges, and industrial facilities. Their all-position welding capability (with proper technique) allows flexibility on job sites where access may be limited.

Pipeline Industry

In pipeline construction and maintenance, weld quality directly impacts safety, efficiency, and longevity. E7018 rods are commonly used in the root pass and fill layers for carbon steel pipelines transporting oil, gas, and water.

They produce welds with excellent mechanical properties capable of withstanding fluctuating pressures and temperatures. Their low moisture content (when properly stored) reduces porosity and hydrogen cracking—critical concerns in field welding where environmental conditions can vary widely.

Marine Industry

Marine environments are exceptionally corrosive and mechanically stressful. E7018 rods are used extensively in shipbuilding and offshore platform construction for welding hull sections, propeller shaft supports, deck reinforcements, and underwater structural components.

When combined with proper surface preparation and post-weld treatments, E7018 welds offer strong resistance to saltwater corrosion and fatigue from wave action. Their ability to create dense, slag-free welds enhances watertight integrity and prolongs service life in harsh maritime conditions.

Manufacturing Industry

In general manufacturing, E7018 rods are a go-to choice for fabricating and repairing industrial machinery, conveyors, presses, and material handling equipment. Their balanced performance—offering both ease of use and high weld toughness—makes them suitable for both production and maintenance welding.

Manufacturers appreciate the consistent arc stability and minimal spatter, which reduce cleanup time and improve productivity. Additionally, the welds’ resistance to cracking under thermal cycling and mechanical shock ensures durability in continuous operation settings.

Best Practices for Using E7018 Welding Rods

Important: Despite common misconceptions, E7018 rods are not designed for welding stainless steel. Using them on stainless alloys can compromise corrosion resistance and mechanical performance. For stainless steel applications, use appropriate electrodes such as E308L, E309L, or E316L. Always verify base metal compatibility and adhere to AWS (American Welding Society) standards for optimal results and safety.

Stainless Steel Welding Rod E7018: Specifications & Features

E7018 welding rods are high-performance, low-hydrogen electrodes widely used in structural and industrial welding applications. Despite the "E7018" designation typically referring to carbon steel electrodes, they are sometimes used in conjunction with stainless steel projects—particularly for joining carbon steel to stainless or in hybrid applications where strength and crack resistance are critical. These rods are engineered to withstand extreme thermal stress, resist moisture absorption, and deliver superior weld integrity, making them a preferred choice for demanding environments.

Diameter Options

E7018 rods are available in a range of diameters to suit various welding tasks and material thicknesses. The diameter selected directly impacts weld penetration, deposition rate, and compatibility with welding equipment.

• Common sizes include 1/16 inch (1.6 mm) and 3/32 inch (2.4 mm), with larger diameters like 1/8 inch (3.2 mm) used for heavy-duty applications
• Thinner rods (e.g., 1/16") are ideal for thin base metals and low-current applications
• Larger diameters (e.g., 3/32" or 1/8") are better suited for thick materials and higher amperage settings

Tip: Always match rod diameter to base metal thickness and power source capabilities for optimal results.

Material Composition

The E7018 electrode features a core wire made from low-hydrogen, alloyed steel, designed to minimize the risk of hydrogen-induced cracking—a common issue in high-strength welds.

• The flux coating contains iron powder, aluminum silicate, calcium carbonate, and titanium dioxide, which stabilizes the arc and enhances weld metal deposition
• This coating produces a smooth, slag-covered weld bead that is easy to clean and exhibits excellent fusion characteristics
• Low hydrogen content (<1 ml/100g of weld metal) ensures high resistance to cracking in restrained joints or low-alloy steels

Note: While not made of stainless steel, E7018 rods are often used in mixed-metal applications involving stainless components.

Operating Current & Amperage Range

E7018 rods are versatile in terms of power source compatibility, working efficiently on both AC and DC (DCEN or DCEP), though DCEP is preferred for best performance.

• 1/16 inch rod: 70–90A (DC), 90–120A (AC)
• 3/32 inch rod: 150–190A (DC), 130–150A (AC)
• Higher amperage increases deposition rate but requires proper heat control to avoid burn-through
• Always follow manufacturer guidelines and preheat thick sections when necessary

Best practice: Use DCEP (electrode positive) polarity for deeper penetration and smoother arc stability.

Mechanical Properties

The E7018 electrode is named for its mechanical strength: "E" for electrode, "70" for 70,000 PSI tensile strength, "1" for all-position welding, and "8" for low-hydrogen, iron powder coating.

• Ultimate Tensile Strength: 70,000–80,000 PSI (480–550 MPa)
• Yield Strength: Minimum 58,000 PSI (400 MPa)
• Elongation: 20–30%, indicating good ductility and ability to absorb energy without fracturing
• Impact Toughness: High resistance to shock and low-temperature cracking (typically tested at -20°F/-29°C)

Key benefit: Excellent performance in structural, seismic, and pressure vessel applications.

Professional Recommendation: Store E7018 rods in a heated quiver or rod oven (at 250–300°F / 120–150°C) to maintain their low-hydrogen properties. Exposure to moisture can compromise weld integrity and lead to porosity or cracking. Always follow proper preheating and interpass temperature controls for thick or high-carbon steels.

Additional Considerations for Optimal Performance

• All-Position Welding: E7018 rods are classified for use in all positions (flat, horizontal, vertical, overhead), though technique and travel speed must be carefully controlled
• Slag Removal: The flux coating forms a protective slag layer that must be chipped off after welding and before subsequent passes
• Weld Appearance: Produces smooth, uniform beads with excellent profile and minimal spatter
• Code Compliance: Meets AWS A5.1 standards and is widely accepted in structural, pipeline, and pressure vessel codes (ASME, API, etc.)
• Storage Requirements: Sensitive to moisture—always re-bake if exposed to humid conditions (typically 700–800°F for 1–2 hours)

How to Choose the Right E7018 Stainless Steel Welding Rod

Selecting the appropriate E7018 stainless steel welding rod is essential for achieving strong, ductile, and corrosion-resistant welds in demanding applications. While E7018 rods are renowned for their excellent mechanical properties and low hydrogen characteristics, choosing the correct variant requires careful consideration of several technical and environmental factors. This comprehensive guide explores the key criteria for selecting E7018 rods to ensure optimal weld integrity, performance, and safety.

Important Note: E7018 electrodes are typically designed for carbon and low-alloy steels, not stainless steel. True stainless steel welding rods are classified under the E3XX series (e.g., E308, E309). If you're welding stainless steel, verify whether you need an E7018 for carbon steel joints or a proper stainless steel electrode. This guide assumes use of E7018 on compatible base metals.

Key Factors in Selecting E7018 Welding Rods

1. Welding Position and Electrode Design
   • The American Welding Society (AWS) classifies welding positions as flat (1G/1F), horizontal (2G/2F), vertical (3G/3F), and overhead (4G/4F).
   • E7018 rods are generally considered all-position electrodes, meaning they can be used effectively in flat, horizontal, vertical up/down, and overhead welding.
   • However, performance can vary between manufacturers. Premium low-hydrogen variants are formulated with specialized flux coatings that provide excellent arc stability and slag control in vertical and overhead positions.
   • Always check the manufacturer’s specifications to confirm position suitability, especially for critical or high-stress joints.
2. Flux Coating Composition and Thickness
   • The thick, iron powder-based flux coating on E7018 rods plays a crucial role in arc stability, metal deposition rate, and weld bead appearance.
   • This coating produces a protective gas shield (primarily CO₂ and H₂) and forms a slag layer that slows cooling, allowing gases to escape and reducing porosity.
   • Thicker coatings increase deposition efficiency and improve bead smoothness but produce more slag, requiring thorough post-weld cleaning.
   • Low-hydrogen coatings minimize moisture absorption, which helps prevent hydrogen-induced cracking—especially important in high-strength steels and thick sections.
3. Tensile Strength and Mechanical Properties
   • The "70" in E7018 indicates a minimum tensile strength of 70,000 psi (485 MPa) in the weld metal.
   • The "1" denotes suitability for all welding positions, and the "8" refers to the low-hydrogen potassium-based flux coating and the need for AC or DC+ power sources.
   • E7018 welds offer high ductility, good impact toughness (especially at low temperatures), and excellent crack resistance—making them ideal for structural steel, pressure vessels, and seismic applications.
   • Always match or exceed the tensile strength requirements of the base metal and project specifications (e.g., AWS D1.1 for structural welding).
4. Material Compatibility and Base Metal Type
   • E7018 rods are best suited for welding carbon steels and low-alloy steels such as A36, A572, and A514.
   • They are not recommended for welding stainless steel, aluminum, or non-ferrous metals. For stainless applications, use E308, E309, or E316 series electrodes.
   • Ensure compatibility with the base metal’s chemistry and strength grade. Mismatched electrodes can lead to brittle welds, cracking, or premature failure.
   • For dissimilar metal joints (e.g., carbon steel to high-strength steel), consult welding procedure specifications (WPS) or engineering guidelines.
5. Preheat and Interpass Temperature Control
   • Proper temperature management is critical when using E7018 rods due to their low-hydrogen formulation and use on higher-strength or thicker materials.
   • Preheat temperature reduces cooling rate, prevents martensite formation, and allows hydrogen to escape. Typical preheat ranges are 200–400°F (95–200°C), depending on material thickness, joint design, and ambient conditions—not 15–25°C as sometimes misunderstood.
   • Interpass temperature must be maintained within specified limits (usually 50–100°F above preheat) to avoid excessive heat input or quenching effects.
   • Always follow AWS D1.1 or project-specific welding codes. Use contact thermometers or temperature crayons for accuracy.

Expert Tip: Store E7018 electrodes in a heated rod oven (250–300°F / 120–150°C) after opening to preserve their low-hydrogen properties. Never leave them exposed to humid air for more than 1–2 hours, as moisture absorption can lead to hydrogen cracking in critical welds.

Additional Best Practices for E7018 Welding

• Always use a DC+ (direct current electrode positive) or AC power source as specified by the electrode manufacturer.
• Use a short arc length and proper travel speed to minimize slag entrapment and ensure good fusion.
• Chisel or wire brush slag thoroughly between passes to prevent inclusions.
• Follow a qualified Welding Procedure Specification (WPS) for critical applications.
• Inspect welds for undercut, porosity, and cracking using visual or NDT methods as required.

Choosing the right E7018 welding rod involves more than just reading the label—it requires understanding the interplay between electrode characteristics, base metal properties, and environmental conditions. By carefully evaluating welding position, coating type, tensile strength, material compatibility, and temperature control, you can ensure durable, high-quality welds that meet structural and safety standards. When in doubt, consult welding engineers or refer to AWS standards to make informed decisions.

Frequently Asked Questions About E7018 Welding Rods

E7018 welding rods are among the most popular electrodes used in structural and industrial welding due to their excellent combination of strength, durability, and ease of use. These low-hydrogen, iron powder, shielded metal arc welding (SMAW) rods produce high-quality welds with superior tensile strength—typically around 70,000 psi—making them ideal for critical applications.

• Strong & Ductile Welds: E7018 rods create welds that are not only strong but also exhibit good impact resistance, even in cold environments, making them suitable for seismic zones and outdoor construction.
• Smooth Arc & Easy Slag Removal: They offer a stable arc with minimal spatter and produce a thin, self-peeling slag that simplifies cleanup and reduces post-weld grinding.
• Versatile Positional Welding: Designed for use in all positions (flat, horizontal, vertical, and overhead), they are favored in fieldwork and fabrication shops.
• Temperature Resilience: These rods maintain consistent performance across a wide range of ambient temperatures, enhancing reliability in both hot and cold climates.
• Reduced Risk of Cracking: The low-hydrogen coating helps prevent hydrogen-induced cracking, especially in thick sections or high-strength steels.

Because of these benefits, E7018 rods are commonly used in pipeline welding, structural steel, pressure vessels, and bridge construction.

While E7018 rods are specifically formulated for low-hydrogen welding on carbon and low-alloy steels, they are compatible with a wide range of ferrous materials, particularly where high strength and crack resistance are required.

• Mild Steel (Carbon Steel): This is the most common application. E7018 rods provide excellent fusion and mechanical properties on materials like A36 and other structural steels.
• Low-Alloy Steels: Suitable for many high-strength low-alloy (HSLA) steels such as A514 and A572, especially when preheating and proper procedures are followed.
• Cracked or Repaired Castings: Often used in repair welding on cast steel or malleable iron components due to their controlled hydrogen content and ductility.
• Not Recommended for Stainless Steel: Despite some confusion, E7018 is not a stainless steel electrode. It should not be used on austenitic stainless steels like 304 or 316. For stainless, use E308L-16 or similar electrodes.

Always match the electrode to the base metal grade and consult welding procedure specifications (WPS) for critical applications. Preheating may be required for thick sections or high-carbon materials to prevent cracking.

The optimal diameter of an E7018 welding rod depends on several key factors including base metal thickness, joint design, welding position, and available amperage. Selecting the right size ensures proper penetration, arc stability, and control.

A general rule of thumb is to use approximately 1 mm of electrode diameter per 50 amps of welding current. However, always refer to the manufacturer’s recommendations and perform test welds to fine-tune settings. Using too large a rod on thin metal can cause burn-through, while too small a rod on thick material may result in insufficient penetration.

Yes, E7018 welding rods have a limited shelf life and must be handled carefully due to their hygroscopic nature—meaning they readily absorb moisture from the air. Once exposed, moisture compromises the low-hydrogen properties of the flux coating, increasing the risk of hydrogen-induced cracking, porosity, and weak welds.

• Shelf Life: Unopened vacuum-sealed packages typically remain viable for up to two years. Once opened, E7018 rods should be used within 8–12 hours if left in humid conditions, or stored in a rod oven.
• Proper Storage: After opening, store rods in a heated holding oven set between 250°F and 300°F (120°C–150°C) to maintain dryness.
• Rebaking: If rods are exposed to moisture, they can often be rebaked in a drying oven at 700°F–800°F (370°C–425°C) for 1–2 hours, depending on manufacturer guidelines. However, repeated rebaking degrades the flux coating.
• Visual Inspection: Discard rods with cracked, chipped, or powdery coatings, or those that produce excessive spatter and porosity during welding.

To ensure weld integrity, always check the manufacturer’s date on the packaging and avoid using rods that have been improperly stored or exposed to high humidity for extended periods. Proper handling is crucial for maintaining the high performance and safety standards expected from E7018 electrodes.