The Solution | Specialized Tools Designed for High-Si Alloys：CVD Diamond-Coated End Mills

High Silicon Aluminum Alloy Machining: When Tool Wear Becomes a Cost Crisis

As machining professionals, we all know that aluminum alloys are generally considered “easy to cut.” But when it comes to high-silicon aluminum alloys (Si > 12%), especially those used in engine block manufacturing like ADC12, the story changes dramatically.

Let’s take a real-world case:

🔧 Scenario: Face Milling & Drilling of Die-Cast Engine Blocks (ADC12)

A CNC machining plant was tasked with face milling and drilling operations on die-cast engine blocks made from ADC12 aluminum alloy, which contains 12–15% silicon content. While this improves casting performance and thermal expansion properties, it introduces a serious challenge for cutting tools.

⚠️ The Hidden Problem: Severe Abrasive Wear Caused by Hard Silicon Particles

The root cause? Hard silicon particles (HV1400) embedded in the aluminum matrix act as abrasive agents, leading to rapid tool degradation — particularly in the form of crater wear on the rake face.

Even tools coated with standard PCD (Polycrystalline Diamond) or diamond-like coatings experience micro-chipping at the cutting edge, significantly shortening their lifespan.

📉 Real Impact:

• A φ20mm endmill lasted less than 15m² of cutting area
• Compared to over 80m² when machining standard aluminum alloys
• Tool life reduced to just 1/5

💸 Financial Loss:

• Single tool cost: ¥34.5 per unit
• Standard aluminum tool cost: ¥6.8 per unit
• That’s over 5x the cost per part

🧪 Why This Happens: Understanding the Mechanism

High-silicon aluminum alloys contain primary silicon crystals, which are extremely hard and brittle. These particles:

• Act like tiny grinding wheels during cutting
• Cause accelerated abrasion wear on the tool’s rake and flank faces
• Lead to edge chipping, especially under interrupted cutting conditions
• Reduce tool life dramatically even at lower cutting speeds

Standard PCD tools, while excellent for non-abrasive aluminum alloys, are not designed to withstand such aggressive abrasive action.

✅ The Solution: Specialized Tools Designed for High-Si Alloys

At SDFTools, we understand the challenges of high-silicon aluminum machining. Our advancedDiamond-Coated End Mills and specially engineered carbide substrates offer:

• Superior abrasion resistance
• Enhanced edge toughness to resist micro-chipping
• Optimized tool geometry for stable cutting performance
• Significantly extended tool life compared to standard solutions

We’ve helped multiple customers reduce tool costs by up to 70% and increase productivity through longer tool change intervals.

🔬 Technical Insight: Key Factors for Success

📈 Call to Action: Optimize Your High-Si Aluminum Machining Process

If you’re facing similar issues in your production line — whether it’s engine blocks, transmission cases, or other die-cast aluminum components with high Si content — we can help you find the right tooling solution.

👉 Visit us at https://sdftools.com/customize/

Let’s turn your costly tool wear issue into a competitive advantage — together.