A4 Stainless Steel (ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80) is specified for marine, coastal and chemical applications. When hilti hda-t self-undercutting mechanical anchors are specified in this grade, the dimensions remain per Trade series (Hilti HDA-T); the material determines corrosion behavior (superior, including marine and chloride environments) and the service temperature range (approx. -200 °C to +400 °C, subject to the property class and the joint). Both are covered below with the size table.
Why Choose A4 Stainless Steel for Hilti HDA-T Self-Undercutting Mechanical Anchors
Specified for marine, coastal and chemical applications. For hilti hda-t self-undercutting mechanical anchors, this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Superior, including marine and chloride environments |
Galvanic & Galling Considerations
Two important notes for stainless hilti hda-t self-undercutting mechanical anchors: (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.
Comparable Grades
For Hilti HDA-T Self-Undercutting Mechanical Anchors, the alternative stainless grade is A2 (304). A2 (304) suits general indoor and outdoor service; A4 (316) adds molybdenum for marine and chloride environments. Where higher strength matters more than corrosion, switch to plated alloy-steel class 8.8 or 10.9.
Using Stainless Fasteners in Aluminum
Stainless steel is more noble than aluminum, so in the presence of an electrolyte — rain, condensation, salt spray — the aluminum becomes the anode and corrodes at the joint. The effect is driven by the area ratio: a small stainless fastener in a large aluminum section is normally acceptable, while a large stainless fastener in thin aluminum is not. Where the joint is wet, isolate the two metals with a coated or nylon washer and a sealant, or specify an aluminum or coated fastener instead.
Sizes of Hilti HDA-T Self-Undercutting Mechanical Anchors Available in A4 Stainless Steel
| Anchor size | Available embedment options (mm) | Maximum fixture thickness options (mm) | Finish | Base material | Load cases |
|---|---|---|---|---|---|
| M10 | 100 / 125 / 190 / 250 | 20 / 30 / 40 / 50 / 60 / 100 | electro-zinc plated, minimum 5 u00b5m | cracked and non-cracked concrete | static / dynamic / seismic |
| M12 | 100 / 125 / 190 / 250 | 20 / 30 / 40 / 50 / 60 / 100 | electro-zinc plated, minimum 5 u00b5m | cracked and non-cracked concrete | static / dynamic / seismic |
| M16 | 100 / 125 / 190 / 250 | 20 / 30 / 40 / 50 / 60 / 100 | electro-zinc plated, minimum 5 u00b5m | cracked and non-cracked concrete | static / dynamic / seismic |
| M20 | 100 / 125 / 190 / 250 | 20 / 30 / 40 / 50 / 60 / 100 | electro-zinc plated, minimum 5 u00b5m | cracked and non-cracked concrete | static / dynamic / seismic |
