Structural design.
Material + geometry.
Engineered to last.
Designing parts for strength and stiffness requires balancing material properties with geometric efficiency. Cross-section, ribs, fillets, material grade together determine real-world performance.
Key principles.
I, T, box
Hollow cross-sections (box, tube) give same stiffness with less material. I-beam optimal for bending. Solid blocks waste material.
Avoid sharp corners
Sharp internal corners concentrate stress 3-5×. Generous fillets (R=0.2× section) reduce concentration to 1.5×.
60% wall thickness
Ribs perpendicular to deflection direction add stiffness without mass. Standard rule: rib thickness 60% of base wall.
Higher cost works
7075-T6 vs 6061: 80% stronger. Inconel vs 4140: better at temperature. Match grade to need.
Cyclic loading
For cyclic loads, fatigue limit matters not yield. Steel ~50% UTS, aluminum no true limit (use endurance).
Long thin members
Compression members at risk. Critical load = π²EI/L². Add lateral support if needed.
FAQ
Static vs fatigue strength?
Static: yield/UTS limits. Fatigue: 30-50% of yield for 10⁷ cycles. Cyclic loading dominated by fatigue.
Higher strength = better always?
No. Higher strength often less ductile, more notch-sensitive. For impact loads, balanced strength and ductility better than max strength.
Composite materials?
CFRP much stronger per weight, expensive. Use for weight-critical applications (aerospace, racing).
FEA analysis support?
We refer to engineering partners for FEA analysis. Most parts manufactured per drawing; FEA validation by customer or designer.
Surface finish affects strength?
Yes, especially fatigue. Rough surfaces initiate cracks. Polished or shot-peened surfaces extend fatigue life 2-4×.
Assembly adds weakness?
Fastener holes, welds, joints — stress concentrators. Design joints away from peak stress regions when possible.
Get an instant quote
Send your CAD — we reply with detailed pricing, lead time, and DFM feedback within 4 working hours.
Start quoteTalk to an engineer
WhatsApp our team directly. Most messages answered within 12 minutes during work hours.
Open WhatsAppExplore all services
CNC, 3D printing, injection molding, sheet metal, casting, finishing — one quality system, one partner.
See all services