ASTM F2328
Full Name
ASTM F2328 – Standard Test Method for Determining Decarburization and Carburization in Hardened and Tempered Threaded Steel Bolts, Screws, Studs, and Nuts
Scope
ASTM F2328 is a standard test method used to evaluate the decarburization and carburization of hardened and tempered threaded steel fasteners. Decarburization is the loss of carbon from the surface of the steel, while carburization is the gain of carbon. Both of these conditions can adversely affect the mechanical properties of the fastener, such as strength and fatigue resistance.
Test procedure:
- Sample preparation: select representative samples from the lot of fasteners to be tested.
- Sectioning: cut the samples to expose the threaded portion and the adjacent shank.
- Etching: etch the cut surfaces to reveal the microstructure.
- Examination: examine the etched surface under a microscope to identify decarburization or carburization.
- Measurement: measure the depth of the decarburized or carburized layer.
Decarburization and carburization assessment:
- Decarburization: the presence of a soft, low-carbon layer at the surface of the fastener.
- Carburization: the presence of a hard, high-carbon layer at the surface of the fastener.
Applications – decarburization and carburization testing is used in various industries, including:
- Manufacturing: quality control of threaded steel fasteners.
- Construction: inspection of structural components.
- Automotive: evaluation of critical fasteners in vehicles.
Resources
Keywords
decarburization; carburization; threaded steel fasteners; test method; sample preparation; sectioning; etching; examination; measurement; soft; low-carbon layer; hard; high-carbon layer; quality control; manufacturing; construction; automotive; critical fasteners; testing services; ASTM F2328