316 and 316L stainless steels are both austenitic stainless steels with similar corrosion resistance and mechanical properties, but they have some differences primarily in their carbon content and applications. This comparison will outline their chemical composition, properties, corrosion resistance, welding characteristics, and typical applications.


1. Composición química

The primary difference between 316 and 316L is the carbon content.

Table 1: Chemical Composition

ElementoAcero inoxidable 316Acero inoxidable 316L
Cromo (Cr)16-18%16-18%
Níquel (Ni)10-14%10-14%
Molibdeno (Mo)2-3%2-3%
Carbono (C)≤ 0.08%≤ 0.03%
Hierro (Fe)EquilibrioEquilibrio

2. Propiedades mecánicas

Both grades exhibit similar mechanical properties, but the lower carbon content in 316L often leads to better resistance to corrosion and better weldability.

Table 2: Mechanical Properties

PropiedadAcero inoxidable 316Acero inoxidable 316L
Límite elástico (MPa)290 – 600290 – 600
Resistencia a la tracción (MPa)580 – 750580 – 750
Elongación (%)40% o más40% o más
Dureza (Rockwell B)70-9070-90

3. Resistencia a la corrosión

Both grades offer excellent corrosion resistance in various environments, but 316L has an advantage in certain applications due to its lower carbon content, which reduces the risk of carbide precipitation and intergranular corrosion.

Table 3: Corrosion Resistance

Corrosion TypeAcero inoxidable 316Acero inoxidable 316L
General CorrosionVery goodVery good
Pitting ResistanceExcelenteExcelente
Agrietamiento por corrosión bajo tensiónModeradoBetter resistance
Intergranular CorrosionPossible if improperly weldedLower risk due to lower carbon content

4. Soldabilidad

Weldability is an important factor in the selection of stainless steel grades for construction.

Table 4: Weldability Comparison

RasgoAcero inoxidable 316Acero inoxidable 316L
Soldabilidad generalGood, but needs care to avoid carbide precipitationExcellent, lower carbon reduces risk of carbide formation
Pre-Weld TreatmentGenerally not requiredGenerally not required
Tratamiento post-soldaduraMay require annealing to restore propertiesGenerally does not require post-weld treatment

5. Aplicaciones

The choice between 316 and 316L often depends on specific application requirements, especially regarding corrosion resistance and welding conditions.

Table 5: Typical Applications

Área de aplicaciónAcero inoxidable 316Acero inoxidable 316L
Aplicaciones MarinasBoat fittings, marine hardwareMore commonly used for submerged applications where corrosion is critical
Procesamiento químicoTanks and piping for various chemicalsPreferred in environments with chlorine and high salinity
Food and Pharmaceutical IndustryEquipo de procesamiento de alimentosPreferred for hygienic applications; less likely to corrode or rust
Welding FabricationsStructural applications requiring high strengthUsed for thin-walled sections to reduce distortion during welding
Sector de petróleo y gasValves, piping, and equipmentUsed in environments exposed to corrosive media

Resumen de diferencias

RasgoAcero inoxidable 316Acero inoxidable 316L
Contenido de carbono≤ 0.08%≤ 0.03%
Resistencia a la corrosiónGood, with potential for intergranular corrosionBetter due to lower carbon content
SoldabilidadGood, but care neededExcellent, reduced risk of corrosion
CostoGeneralmente más bajoSlightly higher due to lower carbon content and greater alloying
AplicacionesGeneral purpose applications, marineChlorine and high salinity environments, food/pharma industries

Conclusión

Both 316 and 316L stainless steels are excellent choices for applications requiring high corrosion resistance and good mechanical properties. The selection between them typically revolves around the specific environmental conditions and requirements like welding or susceptibility to intergranular corrosion.

  • Acero inoxidable 316 is suitable for a wide range of applications, but care must be taken during welding and in corrosive environments.
  • Acero inoxidable 316L offers enhanced resistance against intergranular corrosion and is preferred for more demanding conditions, especially when welding is involved.

Selecting the right grade is essential for ensuring the performance and longevity of components in various industries.