BS ISO 185:2020 pdf download.Grey cast irons — Classification.
7 Requirements
7.1 Mechanical properties
The order shall specify, in an unambiguous manner, whether the characterizing property is tensile strength determined on cast samples or Brinell hardness determined on the casting, or both tensile strength and Brinell hardness.
lithe order does not specify the characterizing property, then the manufacturer shall characterize the material according to tensile strength.
7.2 Tensile properties
7.2.1 General
The property values apply to grey cast irons cast in sand moulds or in moulds of comparable thermal behaviour. Subject to amendments to be agreed upon in the order, the property values may be applied to castings obtained by alternative methods.
Tensile properties are dependent upon wall thickness as shown in Table 1. For process quality assurance purposes, standardized 30 mm test bars are commonly used.
NOTE Tensile testing requires sound test pieces in order to guarantee pure uniaxial stress during the test.
7.2.2 Test pieces machined from cast samples
The tensile properties of the eight grades of grey cast iron specified by tensile strength, when determined in accordance with 9d using test pieces machined from cast samples, shall conform to the requirements specified in Table 1.
7.2.3 Test pieces cut from a casting
If test pieces are to be machined from samples cut from a casting, the manufacturer and the purchaser shall agree on:
— the locations on a casting where the samples shall he taken;
— the minimum value or the allowable range of values for the tensile properties, when determined in accordance with 91.
NOTE 1 The properties and the structure of castings are not uniform and depend on the complexity of the castings and their variation in section thickness.
NOTE 2 Tensile properties for test pieces machined from samples cut from a casting arc affected not only by material properties subject of this document) hut also by the local casting soundness (not subject of this document).
The Brinell hardness values of the six grades of grey cast iron specified by hardness, when determined in accordance with 92. shall conform to the requirements specified in Table 2.
NOTE 1 Brinell hardness stated in HBW means under test conditions of 10/3 000 unless different test conditions have been specified.
Minimum and maximum Brinell hardness values for the relevant wall thickness specified by the purchaser shall he mandatory for the castings covered by the order.
If a casting is ordered on the basis of hardness, the relevant wall thickness and the position of the test shall be agreed.
NOTE 2 For a relevant wall thickness t> 80 mm, grades are not classified by hardness.
If it is not possible to use the Brinell test method in accordance with ISO 6506-1. alternative test methods may be used, which shall have correlated values with Brinell hardness.
BS ISO 185 pdf download.