Protecting Your Hardware Molds: Tips to Prevent Rust

Table of Contents :

Chapter 1 : Environment management

Chapter 2. Mold surface protection

Chapter 3. Choose corrosion-resistant materials

Chapter 4.  Standardize daily maintenance and care

Chapter 5. Optimize production process

Chapter 6. Other auxiliary measures

Chapter 7. What are the special precautions for different materials mold/die

Chatper  8  :  Summary  of  Core differences in material maintenance

Regarding how to prevent hardware molds from rusting, combined with practical applications and basic stamping knowledge, we have concluded that corresponding measures can be taken from various aspects such as environmental control, surface treatment, material selection, daily maintenance management, and process optimization to prevent the hardware die from rusting and extend the life of hardware molds as below.

Chapter 1 : Environment management

1.1 Humidity management

The area where the molds are stored needs to be kept dry and not stored in a humid environment (humidity should be controlled below 60%). At the same time, the air humidity can be reduced by installing dehumidifiers, air conditioners, or placing desiccants (such as silica gel). Molds that are not stored for a long time need to be wrapped with anti-rust paper and plastic film to isolate moisture.

1.2 Temperature management

Do not let the die/mould come into contact with condensed water. For example, when the temperature difference between the inside and outside of the workshop is large in winter, the mold needs to be preheated in advance or ventilation needs to be controlled to prevent condensation on the surface.

1.3 Clean environment

Keep the storage workshop clean, do not allow dust, oil and other pollutants to adhere to the mold/die surface, and clean the workbench and storage rack regularly every month.

Chapter 2. Mold surface protection

2.1 Apply rust inhibitor/oil on the surface

After using or before storing the mold, thoroughly clean the oil stains and metal debris on the mold surface, and evenly apply professional rust-proof oil (such as hard film rust-proof oil, thin layer rust-proof oil) or rust inhibitor to form a protective film to isolate the air.

2.2 Electroplating or coating treatment

If necessary, the mold surface can also be electroplated (such as zinc plating, nickel plating) or sprayed with anti-corrosion coating (such as epoxy resin, Teflon), etc., which can also improve the surface mold hardness and corrosion resistance.

2.3 Extension:

Relevant hardware stamping mold industry manufacturers often enhance rust resistance by strengthening surface treatment (such as nitriding, PVD coating).

2.4 Use rust-proof packaging materials

Use relevant rust-proof paper, rust-proof film and other packaging materials to suppress rust on the mold surface by releasing rust-proof gas.

Chapter 3. Choose corrosion-resistant materials

3.1 Mold steel materials selection

Choose steel with strong corrosion resistance (such as stainless steel, high chromium mold steel Cr12MoV, S136, etc.) to reduce the risk of rust from the nature of the mold material.

3.2 Material thermal processing

The hardness and density of the mold surface can be improved through vacuum heat treatment, quenching and other processes, and micropores and corrosion channels can be reduced to ensure process stability.

Chapter 4.  Standardize daily maintenance and care

4.1 Regular cleaning and inspection

After tooling use, clean the stamping waste and lubricant residue on the mold surface in time to avoid long-term adhesion of corrosive substances.

Check whether there are scratches, wear or rust on the mold surface, and repair problems in time (such as grinding and repair welding).

4.2 Lubrication management

Use appropriate lubricants (such as sulfur-free and chlorine-free lubricants) to avoid corrosive components in the lubricant itself. Regularly replace aging lubricants to prevent grease deterioration and accelerate rust.

4.3 Shutdown maintenance

Before long-term shutdown, the mold needs to be fully cleaned and rust-proofed, and the maintenance status should be checked regularly (such as monthly), and anti-rust oil should be reapplied if necessary.

Chapter 5. Optimize production process

5.1 Control corrosion factors during stamping

Avoid using stamping oil containing water or acid during stamping, and choose neutral or weak alkaline lubricants to reduce chemical corrosion.

Clean up metal debris and coolant generated during stamping in time to prevent residual liquid from corroding the mold.

5.2 Process continuity

,minimize the risk of rust caused by environmental exposure during transportation and turnover of the mold during mold processing.

Chapter 6. Other auxiliary measures

Use anti-rust equipment: such as installing anti-rust lamps in the storage area (emitting ultraviolet rays to inhibit mold and rust).

Establish anti-rust ledger: record mold maintenance time, anti-rust treatment method, storage location, etc., for easy traceability and management.

Employee training: Strengthen the training of operators on anti-rust knowledge, standardize daily maintenance procedures, and avoid rust caused by human negligence.

Chapter 7. What are the special precautions for different materials mold/die

7.1. Carbon tool steel molds (such as T8, T10)

Material characteristics: high carbon content, high hardness but poor wear resistance and corrosion resistance, easy to rust, and brittle after heat treatment.

Maintenance focus: After each use, it must be thoroughly cleaned and a thick layer of anti-rust oil (such as calcium-based anti-rust oil) must be applied. Pay special attention to the edges and threaded holes that are prone to water accumulation to avoid edge cracking due to rust.

7.2. Alloy tool steel molds (such as Cr12, Cr12MoV, D2)

Material characteristics: Adding alloy elements such as chromium, molybdenum, and vanadium, the wear resistance and hardenability are better than carbon steel, but the corrosion resistance is still limited, and attention should be paid to surface protection. Maintenance focus: Regularly check the integrity of the surface coating (such as nitride layer, coating), and if there is peeling, timely re-plating (such as PVD coating) is required. Lubrication and cleaning at the same time

Use high-viscosity lubricants (such as molybdenum disulfide grease) to reduce friction heat during stamping and avoid surface oxidation caused by high temperature. When cleaning, use solvent-based cleaning agents (such as aviation gasoline) to thoroughly remove carbon deposits and grease to prevent residual lubricants from carbonizing and wearing the surface.

7.3, stainless steel molds (such as 420SS, S136)

Material characteristics: high chromium content (≥13%), strong corrosion resistance, but poor thermal conductivity, easy to cause high temperature due to friction and cause adhesion wear. Maintenance focus: When stamping non-ferrous metals (such as copper and aluminum), "sticking mold" phenomenon is easy to occur, and residual metal debris will destroy the passivation film and cause rust. Use a copper brush or nylon brush to remove adhesion after each use, and avoid damaging the surface with a wire brush.

7.4 Control lubrication cooling

Select anti-adhesion lubricants (such as graphite emulsion, dimethyl silicone oil) to reduce the friction coefficient; avoid using sulfur-containing cutting fluids during cooling to prevent pitting of stainless steel surfaces.

7.5  Avoid iron ion contamination

Avoid direct contact with carbon steel tools (such as iron fixtures) during storage to prevent iron ions from transferring to the stainless steel surface to form galvanic corrosion.

7.6  High-speed steel molds (such as W18Cr4V, M2)

Material characteristics: high hardness, high wear resistance, high temperature resistance (up to 600℃), but poor corrosion resistance, and high stress after quenching.

Maintenance focus:

7.7 High-speed steel molds are often used for high-temperature stamping (such as hot forging). After use, they need to be slowly cooled to room temperature and then cleaned to avoid surface cracking caused by sudden cooling. After cooling, remove the oxide scale in time (sandblasting can be used), and then apply high-temperature rust-proof oil (such as molybdenum disulfide composite oil).

After long-term use, regular stress relief annealing (such as 160-200℃ insulation for 2 hours) is required to reduce internal microcracks and prevent water accumulation and rust at the cracks. Taiqun Hardware's vacuum heat treatment process can assist this process, and it is recommended to return to the factory for treatment regularly.

7.8  Other special material molds

Carbide molds (such as YG8, YT15) Notes: Extremely brittle, do not use impact tools (such as compressed air direct impact) when cleaning, and need to be brushed lightly with a soft brush; avoid contact with acidic media, wrap with anti-rust paper and store separately when storing to prevent collision with other molds. It is strictly forbidden to use sandpaper or rough tools to wipe the coating surface. After cleaning, check whether the coating has fallen off or bubbling, and re-plating in time to maintain anti-corrosion performance.

Chatper  8  :  Summary  of  Core differences in material maintenance