Significance and Use

This test method covers determination of the total tin in the sample tested and does not apportion the tin to one or the other side of the test specimen. The calculations appearing in Section 27 assume uniform distribution of tin over the two surfaces.

This test method does not differentiate between free tin on the tinplate surface, tin combined with iron in the intermediate alloy layer, or tin alloyed with the steel as a residual tramp element.

1. Scope

1.1 These test methods include four methods for the determination of tin coating weights for electrolytic tin plate as follows:

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

3.1 This test method covers the determination of tin coating weights on steel plate.

10.1 This test method may be used to determine not only the total tin coating weight but also to determine that part of the tin coating which is present as free tin and that part which is present in the alloyed form.

19.1 This test method covers the determination of the total weight of tin carried by a unit area of tinplate.

29.1 This test method is normally applicable to the determination of tin coating weights in the range of 0.50 to 1.50 lb of tin/bb.

Note 4For the determination of the coating weights outside of this range, an iodate solution of appropriate concentration should be prepared so that suitable titrant volumes are obtained. For the determination of low tin coating mass in the range from 0.05 0.49 lb/bb, the number of sample specimens should be adjusted appropriately to maintain a minimum total tin mass equivalent to that present on a 0.50 lb/bb specimen. This test method cannot be used to test single spot tin mass for low tin coating material.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

A599/A599M Specification for Tin Mill Products, Electrolytic Tin-Coated, Cold-Rolled Sheet

A623 Specification for Tin Mill Products, General Requirements

A623M Specification for Tin Mill Products, General Requirements [Metric]

A624/A624M Specification for Tin Mill Products, Electrolytic Tin Plate, Single Reduced

A626/A626M Specification for Tin Mill Products, Electrolytic Tin Plate, Double Reduced

D1125 Test Methods for Electrical Conductivity and Resistivity of Water

Keywords

Bendix method; Coating weight; Constant-current electrolytic method; Electrolytic tin plate; Electrostripping; Hot-dip (galvanized) coatings; Instrumental measurement--metals/alloys; Referee methods; Sellar's method; Tin coating weights; Tin mill products; Titration;

ICS Code

ICS Number Code 25.220.40 (Metallic coatings)

DOI: 10.1520/A0630-03R09

ASTM International is a member of CrossRef.

ASTM A630