Titanium Grade 2 vs Grade 5: Which Do You Need for Your CNC Parts?

This article is part of the CNC Machining Materials Guide: Metals, Plastics & Superalloys on CNX Precision.

Deciding between titanium grade 2 vs grade 5 affects cost, weight, and part life. Both grades come from the same base metal. However, they behave very differently in service. Grade 2 is commercially pure titanium. Grade 5 is the famous Ti-6Al-4V alloy. In this guide, we compare their properties and machining behavior. You will also learn which grade fits aerospace, medical, and industrial parts. Read on to make a confident material choice.

What Is Titanium Grade 2?

Grade 2 belongs to the commercially pure family. It contains about 99.2 percent titanium. Oxygen and iron appear in small amounts. This grade offers excellent corrosion resistance, especially in seawater and chemical media. Moreover, it forms and welds easily. Its yield strength ranges from about 275 MPa to 410 MPa. Therefore, designers use it for heat exchangers, desalination plants, and chemical vessels. Medical instrument housings also use Grade 2.

Because Grade 2 has no alloying additions, its microstructure stays simple. It remains ductile at low temperatures. Furthermore, it resists stress corrosion cracking in most natural environments. These qualities make it a workhorse material for process industries. Fabricators also prefer it when forming complex sheet metal shapes.

Grade 2 resists pitting and crevice corrosion in chloride-rich fluids. It also tolerates oxidizing acids at moderate temperatures. For that reason, chemical plants select it for piping and vessels. Its oxide film self-heals quickly after minor damage. This passive layer is the basis of titanium corrosion performance.

What Is Titanium Grade 5?

Grade 5, or Ti-6Al-4V, is an alpha-beta alloy. Aluminum adds strength. Vanadium stabilizes the beta phase. After annealing, its yield strength reaches about 880 MPa. Consequently, it offers the best strength-to-weight ratio among common titanium grades. Aerospace structures, landing gear, and engine components rely on it. Moreover, medical implant makers use Grade 5 for its biocompatibility. Automotive racing parts also benefit from its stiffness.

When you compare titanium grade 2 vs grade 5, note the heat treatment difference. Grade 5 can be annealed, solution treated, or aged. Aging raises strength even further. However, it also reduces ductility. Therefore, most structural parts use the annealed condition. Implants often use the mill-annealed state with controlled microstructure.

The two grades also differ in density only slightly. Both weigh about 4.5 g/cm3. However, the usable strength differs by a large margin. Therefore, Grade 5 often produces lighter structures. For example, a Grade 5 bracket can replace a heavier Grade 2 part. Weight savings matter in aerospace and motorsport.

Titanium Grade 2 vs Grade 5: A Side-by-Side Comparison

The table below captures the main differences. Use it when you compare titanium grade 2 vs grade 5 for a component.

Each property matters in a different way. First, check the stress levels in your design. Second, check the exposure environment. Third, check the fabrication route. These factors usually decide between titanium grade 2 vs grade 5. Also review the fastener and coating requirements. Some designs need threaded holes that only Grade 5 can support.

CNC Machining Considerations for Both Grades

Titanium is difficult to machine. Its low thermal conductivity traps heat in the tool. Therefore, cutting speeds must stay low. Use sharp carbide tools with generous relief. Also, use high-pressure coolant to carry heat away. Climb milling and constant chip load reduce work hardening.

Grade 2 is gummier than Grade 5. It tends to smear and form long chips. Positive rake angles help. Grade 5 is stronger but more abrasive. It wears tools faster. In both cases, rigid fixtures prevent chatter. When comparing titanium grade 2 vs grade 5 in machining, expect shorter tool life than steel.

Surface finish also differs. Grade 2 can tear if feeds are too light. Grade 5 responds well to light finishing passes with coated carbide. For tapped holes, use roll taps where geometry allows. For deep pockets, use peck milling and sharp end mills. These methods protect thin-wall features and hold tight tolerances.

At CNX Precision, we machine both grades on 3/4/5-axis centers. We hold tight tolerances on thin-wall titanium parts. For example, we produce aerospace brackets, surgical instruments, and racing components. Every batch includes material certificates and inspection reports.

Tool selection starts with sharp, positive geometry. Coated carbide extends life at moderate speeds. High-pressure coolant through the spindle prevents built-up edge. In addition, avoid coolant shutdown between passes. Thermal cycling cracks cutting edges. Therefore, keep the process steady from roughing to finishing.

Chip evacuation is critical in titanium. Long chips wrap around the tool and damage the surface. Therefore, use peck cycles in drilling. For milling, climb milling with high flute count tools clears chips quickly. Watch the tool for edge breakdown after every batch.

Fixturing deserves special care. Titanium springs back more than steel. Therefore, support thin sections fully. Use soft jaws or vacuum fixtures for flat parts. Clamping force must resist cutting forces but avoid distortion. Our machinists dial in these variables before production starts.

How to Choose the Right Grade

Before choosing between titanium grade 2 vs grade 5, list the part requirements. Then compare them with the table above. The following rules cover most projects.

• Choose Grade 2 for corrosion-critical, low-stress parts.
• Choose Grade 5 for load-bearing and fatigue-critical parts.
• Choose Grade 2 when welding or forming dominates production.
• Choose Grade 5 when weight reduction matters most.

Cost also differs. Grade 5 usually costs more per kilogram. However, its strength lets designers use less material. Therefore, total part cost can be similar. Our engineers can help you evaluate both options. Send us the drawing and loading conditions.

Surface treatment matters for many parts. Anodizing improves wear and corrosion resistance. Passivation is often specified for medical devices. Grade 5 responds to alpha-case control during machining and heat treatment. Grade 2 accepts simple anodizing for color coding. Therefore, plan the finishing route before you order material.

Frequently Asked Questions

Which is stronger, titanium grade 2 vs grade 5?

Grade 5 is much stronger. Its yield strength is roughly double that of Grade 2. Therefore, Grade 5 suits structural parts that carry high loads. In fact, the annealed condition alone offers more than 800 MPa of yield strength.

Is titanium grade 2 vs grade 5 better for medical implants?

Both grades are biocompatible. However, Grade 5 offers higher strength. Therefore, orthopedic implants, plates, and screws usually use Grade 5. Grade 2 appears in some surgical instruments and low-load devices. Its fatigue strength also suits long-term load bearing in the body.

Does titanium grade 2 or grade 5 cost more?

Grade 5 costs more per kilogram. Alloying elements and processing drive the price. Nevertheless, its strength can reduce overall part weight and size. However, both grades cost far more than steel. Therefore, justify the premium with weight or corrosion benefits.

Ready to start a titanium project? Send your CAD file to CNX Precision. We machine both titanium grade 2 vs grade 5 with proven quality. Request a free quotation today.

For related information, see our guide to cnc machining service and 5-axis cnc machining and cnc milling vs turning and cnc machining tolerances.