ISO 898-5:1998 pdf download.Mechanical properties of fasteners made of carbon steel and alloy steel
1 Scope
This part of ISO 898 specifies the mechanical properties of set screws and similar threaded fasteners not under tensile stresses with nominal thread diameters from 1,6 mm up to and including 24 mm, which are made of carbon steel or alloy steel.
The mechanical and physical properties apply when tested at an ambient temperature of 10 CC to 35 CC and will vary at higher or lower temperatures.
This part of ISO 898 does not apply to set screws requinng special properties such as
— specified tensile stresses (see ISO 898-1);
— weldability;
— corrosion resistance;
— ability to withstand temperatures above + 300 CC or below — 50 CC.
NOTE — Set screws made from free-cutting steel should not be used above + 250 cc.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO 898. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO 898 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards.
ISO 965-3:1998, Iso general purpose metric screw threads —Tolerances — Part 3: Deviations for constructional threads.
ISO 4948-1:1982, Steels — Classification — Part 1: Classification of steels into unalloyed and alloy steels based on chemical composition.
ISO 6506:1981. Metallic materials — Hardness test — Brinell test.
ISO 6507-1:1997, Metallic materials — Vickers hardness test — Part 1: Test method.
ISO 6508:1986. Metallic materials — Hardness test — Rockwell test (scales A - B- C - D - E- F - G - H - K).
6.1 Hardness tests
Hardness tests shall be conducted as near as practicable to the centre position of the point end of the screw. If the maximum hardness as given in table 3 is exceeded, a retest shall be conducted on a cross section 0,5 d back from the point end where d is the nominal thread diameter. In case of doubt, the Vickers hardness test is decisive for acceptance.
Hardness readings for the surface hardness shall be taken on the end of the screw, which will be prepared by slightly grinding or polishing to ensure reproducible readings.
6.1.1 Vickers hardness test
The Vickers hardness test shall be carried out in accordance with the provisions of ISO 6507-1.
6.1.2 Brinell hardness test
The Brinell hardness test shall be carried out in accordance with the provisions of ISO 6506.
6.2 Decarburization test一evaluation of the surface carbon condition
Using the appropriate measuring method (6.2.2.1 or 6.2.2.2 as applicable), the longitudinal section of the thread shall be examined to determine that the height of the zone of base metal (E) and the depth of the zone with complete decarburization (G) are within specified limits, (see figure 1). The minimum values for E and the maximum values for G are specified in table 3.ISO 898-5 pdf download.