Metalworking Fluid Additives
Monoesters, Polyols Esters, Diacid Blends & Monoacids
Metalworking fluid additives help formulators manage friction, corrosion, foam, stability, and other performance requirements across metal removal and forming operations. Emery Oleochemicals offers ester-based lubricity additives, dibasic acid blends, and pelargonic acid chemistries for oil-based and water-based formulations.
Compare each additive family below, then work with Emery's technical team to evaluate the right chemistry for your carrier system, operation, metallurgy, and performance targets.
Contact Us today to explore metalworking fluid additives for your formulation.
Metalworking Fluid Additive Solution Selector
| Additive family | Primary formulation benefit | Best-fit fluid type | Emery solution |
| Lubricant esters | Lubricity, friction reduction, film strength, and hydrolytic stability | Oil-based and water-based fluids | DEHYLUB® lubricant esters |
| Dibasic acid blends | Corrosion protection for iron and steel, rust control, foam control, and hard-water stability | Water-based and other aqueous formulations | EMEROX® dibasic acid blends |
| Pelargonic acid | Corrosion inhibition, coupling capability, and lower-foaming performance in suitable derivatives | Primarily water-based formulations using water-soluble amine salts or condensates | EMERY® pelargonic acid |
This selector provides a starting point, not a finished formulation recommendation. Additive performance depends on the complete package, concentration, carrier, water quality, metallurgy, operating conditions, and required approvals.
What Metalworking Fluid Additives Do
Metalworking fluid additives are functional ingredients added to a base fluid to deliver or enhance properties beyond those the carrier provides alone.
Depending on the chemistry, they may support boundary lubrication, corrosion protection, emulsion or coupling behavior, foam control, oxidative stability, and fluid service life.
The OSHA metalworking fluids manual identifies four major fluid classes:
- Straight oils
- Soluble oils
- Semisynthetic fluids
- Synthetic fluids
Each class creates a different starting point for additive selection. Straight oils emphasize lubrication, while water-miscible systems must balance lubrication and cooling with corrosion protection, emulsion stability, water quality, and sump performance.
In a complete formulation, metalworking additives may be used to:
- Reduce friction at the tool-workpiece interface.
- Build film strength under boundary-lubrication conditions.
- Protect freshly machined iron and steel surfaces from rust.
- Support fluid stability in water-based systems.
- Control foam in recirculating or high-agitation equipment.
- Improve compatibility among formulation components.
- Help the fluid perform across the intended temperature, pressure, speed, and load range.
- Support surface finish, tool protection, and downstream processing goals.
No single additive automatically delivers every function. Formulators typically build an additive package around the fluid class, process, metallurgy, water conditions, and required performance profile.
Key Additive Categories in Metalworking Fluids
A metalworking fluid may contain several additive categories, each with a specific job. Common categories include:
- Lubricity additives: Help form a protective film between the tool and workpiece to reduce friction and wear.
- Corrosion inhibitors: Help protect the workpiece, machine tool, and other exposed metal surfaces.
- Extreme-pressure and antiwear additives: Support protection when temperature and load exceed the effective range of boundary lubrication alone.
- Emulsifiers and coupling agents: Help disperse oil-soluble components in water and maintain formulation uniformity.
- Foam-control additives: Limit persistent foam that can interfere with fluid circulation and process control.
- Antioxidants: Help slow oxidative degradation in susceptible base stocks or formulation components.
- Biocides and preservatives: Help manage microbial contamination in water-miscible systems where approved and used appropriately.
Emery's metalworking portfolio focuses on three versatile chemistry families: DEHYLUB® ester additives for metalworking, EMEROX® dibasic acid blends, and EMERY® pelargonic acid. These chemistries can address different but sometimes complementary formulation needs.
Ester-Based Lubricity Additives
Esters are widely used as base-stock components and lubricity additives for metalworking fluids. Their polar ester groups have an affinity for metal surfaces, helping form a lubricating film at the tool-workpiece interface. This boundary film can reduce direct contact, friction, and wear during metal removal or forming.
DEHYLUB® lubricant esters for metalworking fluids are designed to offer:
- High lubricity and friction reduction
- Film strength for metal removal and metal forming applications
- Low odor
- Hydrolytic stability
- Versatility in oil-based and water-based formulations
The broader DEHYLUB® lubricant ester portfolio includes monoesters, diesters, polyol esters, complex esters, and trimellitate esters. Different ester structures and viscosity profiles can serve as base fluids, co-base stocks, lubricity boosters, or other functional components.
Renewable content, biodegradability, and regulatory status also vary by grade, so formulators should confirm the relevant technical and sustainability data for the product under consideration.
Corrosion Inhibitors and Dibasic Acid Blends
Water improves cooling, but it also increases the need for effective corrosion control. Newly machined surfaces can be particularly vulnerable, and the fluid must also protect ferrous components throughout the circulating system.
EMEROX® dibasic acid blends for metalworking fluids combine azelaic acid with other dibasic acids. When neutralized with suitable amines or hydroxides, these blends form salts that provide corrosion protection and rust control for iron and steel in aqueous formulations.
EMEROX® dibasic acid blends may also support:
- Foam control compared with many individual or blended acids.
- Stability in hard-water conditions.
- Corrosion protection in metalworking fluids, metal cleaners, and other aqueous systems.
- Flexible formulation through the selection of the neutralizing component.
Corrosion performance remains system-dependent. The inhibitor package should be evaluated with the intended metal or alloy, neutralizing amine, pH range, water hardness, concentration, and other additives.
Pelargonic Acid in Metalworking Fluids
Pelargonic acid is a saturated, odd-chain C9 monocarboxylic acid. Its single carboxyl group and chain structure give it a different formulation role from dibasic acids, which contain two carboxyl groups.
EMERY® pelargonic acid for metalworking fluids can be reacted with low-molecular-weight amines to produce water-soluble salts and condensates. In suitable formulations, these derivatives may provide:
- Corrosion inhibition
- Coupling capability
- Lower-foaming characteristics
- Water solubility
Pelargonic acid may be considered when a formulator needs a multifunctional monoacid option in a water-based system. The appropriate acid form, amine derivative, neutralization level, and use concentration should be established through formulation testing.
Water-Based vs. Oil-Based Metalworking Fluid Needs
Carrier type changes the formulation environment and the properties that matter most. The fluid class should therefore be one of the first selection decisions.
| Fluid type | Typical formulation priorities | Emery chemistry starting points |
| Straight or neat oil | Lubricity, film strength, base-oil compatibility, viscosity, oxidative stability, residue, and odor | DEHYLUB® lubricant esters |
| Soluble oil | Lubricity plus emulsion stability, corrosion control, water hardness, hydrolytic stability, and foam | DEHYLUB® esters with suitable EMEROX® or EMERY® corrosion-control chemistry |
| Semisynthetic fluid | Balanced cooling and lubricity, component compatibility, corrosion control, low foam, and sump stability | Water-compatible DEHYLUB® esters, EMEROX® dibasic acid blends, and EMERY® pelargonic acid derivatives |
| Synthetic fluid | Corrosion control, coupling, water solubility, low foam, hard-water performance, and lubricity without petroleum oil | EMEROX® dibasic acid blends, EMERY® pelargonic acid derivatives, and compatible ester lubricity additives where appropriate |
These are formulation starting points rather than fixed packages. A chemistry that performs well in one soluble-oil or synthetic system may behave differently when the emulsifier, amine, water source, process temperature, or concentration changes.
How to Select the Right Additive Package
The right package begins with the application, not a preferred ingredient. Before comparing metalworking fluid additives, define the complete performance window.
1. Identify the Fluid Class
Determine whether the finished product will be a straight oil, soluble oil, semisynthetic fluid, or synthetic fluid. Confirm the carrier's polarity and solvency, whether the product will be diluted with water, and the expected in-use concentration.
2. Define the Operation and Severity
Cutting, grinding, drilling, tapping, stamping, drawing, and rolling do not create the same lubrication or cooling demands. Consider contact pressure, tool speed, temperature, feed rate, fluid-delivery method, and the desired surface finish.
| Operation | Common priorities to investigate |
| Cutting, drilling, and tapping | Boundary lubricity, film strength, heat and load, tool protection, and surface finish |
| Grinding and high-speed machining | Cooling, low foam, fluid delivery, hard-water behavior, cleanliness, and corrosion control |
| Stamping, forming, and drawing | Persistent lubricating film, friction reduction, workpiece finish, residue, and downstream cleanability |
| Multi-metal machining | Lubricity across target alloys, ferrous corrosion, nonferrous staining, additive interactions, and downstream compatibility |
3. Confirm Metallurgy
Document every metal the fluid may contact, including the workpiece, tooling, machine, and system components. Ferrous corrosion control does not automatically establish compatibility with aluminum, copper, brass, bronze, or other nonferrous alloys.
4. Evaluate Stability and Plant Conditions
For water-based metalworking fluids, assess hydrolytic stability, pH, reserve alkalinity, water hardness, emulsion or solution stability, microbial-control strategy, and foam under realistic circulation.
For oil-based fluids, assess solvency, oxidative stability, viscosity, volatility, residue, and low-temperature behavior.
5. Review Safety, Regulatory, and Sustainability Requirements
Review the current SDS, regional chemical inventories, customer restrictions, disposal considerations, and any required certifications or listings. When renewable content, biodegradability, or another sustainability attribute is important, verify it for the exact grade instead of assuming that one claim applies to an entire chemistry family.
6. Test the Complete Formulation
Bench screening can help compare corrosion protection, foam, emulsion stability, lubricity, and other properties, but the final package should also be validated under representative operating conditions. Test interactions among additives as well as downstream cleaning, coating, heat treatment, and wastewater processes when relevant.
Why Hydrolytic Stability, Foam, and Odor Matter
These secondary criteria can determine whether a technically promising additive works in the finished fluid.
- Hydrolytic stability: An ester used in a water-containing system must resist breakdown over the intended service conditions. Changes caused by hydrolysis can affect acidity, stability, and lubricating performance.
- Foam control: High-pressure delivery, agitation, soft water, and formulation interactions can generate foam. Persistent foam may disrupt fluid circulation, tank capacity, process visibility, and consistent delivery to the work zone.
- Odor: Raw-material odor and odors that develop during use can affect handling and plant acceptance. Evaluate odor in the finished concentrate and diluted working fluid over the expected service interval.
DEHYLUB® esters are positioned for low odor and hydrolytic stability, while neutralized EMEROX® dibasic acid blends and suitable EMERY® pelargonic acid derivatives can support lower-foam water-based formulations.
Work With Emery Oleochemicals
Emery combines more than 185 years of oleochemical experience with over 65 years of ester technology expertise. Using proprietary natural-based and synthetic lubrication technology, our Bio-Lubricants team supports formulators through a broad chemistry portfolio, application-development capabilities, and Technical Centers of Excellence in the United States and Germany.
We can help you evaluate metalworking additives around your fluid class, operation, metallurgy, performance objectives, and sustainability requirements. Product availability, specifications, certifications, and regulatory status should be confirmed for the intended market and application.
Contact Us today and we'll connect you with the right team.
Frequently Asked Questions About Metalworking Fluid Additives
What are metalworking fluid additives?
Metalworking fluid additives are functional ingredients blended into straight oils, soluble oils, semisynthetic fluids, or synthetic fluids to improve properties such as lubricity, corrosion protection, coupling, foam control, oxidative stability, and fluid life.
Which additives improve lubricity in metalworking fluids?
Ester additives are commonly used to improve boundary lubricity. Their polar groups interact with metal surfaces and help form a film that reduces friction at the tool-workpiece interface. The appropriate ester depends on the carrier, viscosity target, operation, metallurgy, temperature, and other formulation components.
What is the difference between a lubricity additive and a corrosion inhibitor?
A lubricity additive primarily helps reduce friction and surface contact, while a corrosion inhibitor helps protect metal from chemical attack or rust. Some chemistries can contribute more than one function, but each benefit should be confirmed in the finished formulation.
How do I choose additives for a water-based metalworking fluid?
Begin with the fluid class, metallurgy, operation, water hardness, pH, and dilution range. Then evaluate lubricity, hydrolytic stability, corrosion control, coupling, foam, microbial strategy, and compatibility with the full additive package under representative use conditions.
Why is hydrolytic stability important in ester additives?
Hydrolytic stability indicates how well an ester resists reaction with water. In a water-based metalworking fluid, greater resistance to hydrolysis can help limit changes in acid value and preserve formulation stability and lubricating performance over time.
Can one additive package work for every metalworking operation?
No. A package developed for grinding may not provide the film strength required for severe forming, while a package designed for ferrous metals may not meet nonferrous staining requirements. Selection and testing should reflect the specific fluid class, process, alloys, equipment, and downstream steps.
Formulating a metalworking fluid? Tell our Bio-Lubricants team about your requirements. Contact Us