Foreword
This document is prepared in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part 1: Structure of standardization documents and drafting rules".
Drafting.
1 Scope
This document specifies the classification of magnesium and magnesium alloy hot extrusion bar, quality assurance, requirements, test methods, inspection rules and marks, packaging, transportation, storage and quality certificate and order form (or contract) content.
This document applies to magnesium and magnesium alloy hot extruded round bar, square bar, hexagonal bar (hereinafter referred to as bar).
2 normative reference documents
The content of the following documents through the normative references in the text and constitute the essential provisions of this document. Among them, note the date of the cited documents
The date of the referenced documents, only the date of the corresponding version applies to this document; do not note the date of the referenced documents, the latest version (including all the revision of the list) applies to this document.
GB/T 3499 Primary magnesium ingot
GB/T 4297 deformed magnesium alloy low times the organization test method
GB/T 5153 deformed magnesium and magnesium alloy grades and chemical composition
GB/T 8170 Numerical modification rules and limit values of the representation and determination
GB/T 13748 (all parts) magnesium and magnesium alloy chemical analysis methods
GB/T 16865 deformation of aluminum, magnesium and its alloy processing products with tensile test specimens and methods
GB/T 17432 deformed aluminum and aluminum alloy chemical composition analysis sampling method
GB/T 32792 magnesium alloy processing products packaging, marking, transportation, storage
YS/T 627 deformed magnesium and magnesium alloy round cast ingot
ISO 20258 Magnesium-lithium alloy Determination of lithium content Inductively coupled plasma emission spectrometry
This document does not require the definition of terms and definitions.
4 Classification
4.1 Product classification
Bar grades and states should be in line with the provisions of Table 1. Need other grades, states, should be negotiated between the supply and demand, and in the order form (or
contract) in the order form.
4.2 Product markings
The markings of the bars are indicated in the order of product name, standard number, grade, state and specification.
5 Quality Assurance
5.1 Quality assurance of raw materials
The dimensional deviation, low-frequency organization and appearance quality of ingots for bar production shall conform to the provisions of YS/T 627.
5.2 Production process assurance
5.2.1 The production equipment and extrusion process shall be used to effectively ensure the quality of bars, and the extrusion ratio shall not be less than 6.
5.2.2 for forgings with low times the organization of the bar should be tested oxide film, oxide film shall comply with the provisions of Table 2.
6 requirements
6.1 Chemical composition
AM91M, VW84N, VW93M, VW94M, VW92M, WN54M, LZ91N, LA93M, LA93Z grade chemical composition should comply with the provisions of Table 3, Mg9999 chemical composition should comply with the provisions of GB/T 3499, other grades of chemical composition should comply with the provisions of GB / T 5153.
6.2.2 Bending degree
For the diameter of not more than 10mm bars, allowing the use of light pressure can be eliminated bending, other specifications of the bar curvature should be consistent with
6.2.3 Twisting degree
Square bar, hexagonal bar twist degree shall comply with the provisions of the ordinary level in Table 6, the demand side has other levels or special requirements, the supply and demand sides shall
Negotiate and specify in the order form (or contract).
6.2.4 Allowable deviation of chamfer radius
The allowable deviation of the chamfer radius of the square bar and hexagonal bar shall conform to the provisions of Table 7, and when the demand side has other grades or special requirements, the supply and demand sides shall negotiate and specify in the order form.
If the demander has other grades or special requirements, both the supplier and the demander shall negotiate and specify in the order form (or contract).
6.2.5.1 The deviation shall be +20mm for the bars delivered in fixed length or double length, and 5 mm of sawing shall be left for each double length when delivered in double length.
6.2.5.2 Non-scaled delivery of bars, when the bar diameter is not greater than 50 mm, the delivery length should be 1000 mm ~ 6000 mm; diameter
Greater than 50 mm, the delivery length should be 500 mm ~ 6000 mm.
6.2.6 Cutting slope
Both ends of the bar should be cut flush, the slope of the cut should not exceed 3 °.
6.3 Room temperature tensile mechanical properties
6.4 Low times the organization
6.4.1 bar diameter of not less than 20mm should be low times the tissue test, the demand side of the diameter of less than 20mm bar low times the tissue requirements
When the supply and demand should be negotiated between the two sides, and specified in the order form (or contract).
6.4.2 low times on the specimen should not be cracks, cracks, pores, shrinkage, inclusions, bright rings and large grains and other defects that undermine the continuity of the metal.
6.4.3 There may be a layer on the low-frequency specimen with a depth of not more than half of the diameter deviation, and if the demander requires no layer, it shall be stated in the order form (or contract).
contract).
6.4.4 ZK61M alloy bar shall be inspected for coarse crystal ring, and the depth of coarse crystal ring shall not be greater than 5 mm.
6.5 Appearance quality
6.5.1 The surface of the bar should be clean, there should be no inspection and polishing can not be removed from the cracks, scars, corrosion spots, a variety of indentation and reflect the bar
Internal cracks in the concentration of bright circle. Polishing can remove the cracks, scars, corrosion spots and other defects should be polished and repaired before oxidation color.
But the grinding depth should not be greater than the maximum deviation of the bar diameter allowed, and should be polished with sandpaper after finishing. Cracks should not be polished.
6.5.2 The surface of the bar should not affect the user's use of pressure, bruises, pressure pits, bubbles, pores, abrasions and scratches and other defects, the depth of defects should not exceed the allowable negative deviation of the diameter. For the diameter of less than 160mm bars, the depth of extrusion marks should not exceed 0.1mm, for the diameter of not
Less than 160mm bars, the depth of extrusion marks should not exceed 0.3mm.
6.5.3 bar surface oxidation treatment is appropriate, the oxidation layer should be intact, not exposed to the base metal, not off. If the oxidation treatment is not carried out, the bar
The other anti-corrosion protection measures shall be determined by mutual agreement between the supply and demand, and clear in the order form (or contract).
7 Test methods
7.1 Chemical composition
7.1.1 Except for LA93Z, LZ91N, LA93M other alloy bar chemical composition analysis and arbitration according to GB/T 13748 (all parts)
The method specified.
7.1.2 LA93Z, LZ91N, LA93M alloy bars in addition to the chemical composition of the element Li analysis and arbitration according to GB/T 13748 (all parts).
Part), the chemical composition analysis and arbitration of Li elements in accordance with ISO 20258 methods.
7.1.3 The chemical composition of the bar sampling should be consistent with the provisions of GB/T 17432.
7.1.4 Analysis of the value of the determination should be used to modify the comparison method, the value of the rules of modification according to the relevant provisions of GB / T 8170, the number of modifications should be
GB / T 3499, GB / T 5153 and Table 2 of the limit of the number of consistent.
7.2 Dimensional deviation
7.2.1 The cross-sectional dimensions of the bar should be measured using a gauge with an accuracy of not less than 0.02mm.
7.2.2 Bar bending measurement, the bar on the platform, by self-weight to achieve stability, the 1m ruler placed on the surface of the bar.
Measure the maximum gap between the bar surface and the ruler (hs), or measure the maximum gap between the bar bottom surface and the platform along the length of the bar.
7.2.3 When measuring the twist degree of a square bar or hexagonal bar, a plane of the bar is placed on the platform, and one end of the bar is placed against the platform, and the bar is stabilized by its own weight.
When the bar is stabilized by its own weight, the gap values T1 and T2 between the two ends of the bar and the platform are measured, as shown in Figure 2.
The difference between T2 and T1 is the twist degree value of the bar. The difference between T2 and T1 is the torsional twist value of the bar. It can be checked by calipers, stoppers or special tools.
7.2.4 When measuring the slope of the cut, the bar is placed on the inspection platform, and after the bar is stabilized, the angle between the end face of the bar and the inflection scale is measured with the inflection scale.
7.2.5 Other external dimensions can be measured by straight edge, meter, tape measure and stopper, etc.
7.3 Mechanical properties
The mechanical properties of the bar test according to the method specified in GB/T 16865.
7.4 Low-frequency organization
Bar low times the organization of the test according to GB / T 4297 method.
7.5 Appearance quality
The appearance of the bar quality with visual inspection. Depth of defects can not be determined, the grinding method can be used to measure.
8 inspection rules
8.1 Inspection and acceptance
8.1.1 Bar shall be inspected by the supplier to ensure that the quality of the product conforms to the provisions of this document and the order form (or contract), and fill in the quality certificate.
Certificate of quality.
8.1.2 The demander shall inspect the products received according to the provisions of this document. If the inspection result is different from the provisions of this document and the order form (or contract)
If it is not in conformity with the provisions of this document and the order form (or contract), it shall be put forward in writing to the supplier, and the supply and demand sides shall negotiate to solve the problem. Objections belonging to the appearance quality and dimensional deviation shall be raised within one month from the date of receipt of
Within one month from the date of receipt of the product, other performance objections should be raised within three months from the date of receipt of the product. For arbitration, the supply and demand
Both parties shall jointly conduct arbitration sampling at the demand side.
8.2 Group Batch
The bars shall be submitted in batches for acceptance, and each batch shall be composed of the same alloy grade, state and specification, with unlimited batch weight.
8.3 Inspection items
Each batch of bars should be factory inspection, inspection items should include chemical composition, dimensional deviation, room temperature tensile mechanical properties, low times the organization and external
The inspection of the appearance quality.
6.3 7.3
Low times the organization
Extrusion end, each batch (or heat treatment furnace) by the number of roots to take 10%, not less than 2, each taking a sample
6.4 7.4
Appearance quality root-by-root inspection 6.5 7.5
8.5 Determination of test results
8.5.1 When the chemical composition of any specimen fails, the bar can be distinguished from the melt time, the specimen is judged to represent the melt time bar failed, the other melt time
Bar test in turn, the melt time by time to determine. Can not distinguish between the melt sub-judgment of the batch of bars failed.
8.5.2 If the dimensional deviation of any bar does not pass, the bar is judged to be unqualified.
8.5.3 Any specimen of mechanical properties failed, should be taken from the batch (or heat treatment furnace) in another double the number of specimens (including the original
Failed bar) to repeat the test. Repeat test results are all qualified, then the batch (or heat treatment furnace) bars qualified. If the repeat test results
If the results of the repeat test still have samples failed, the batch (or heat treatment furnace) bar is judged to be unqualified. By mutual agreement between the supply and demand side allows the supplier to test root by root, root by root
Judgment.
8.5.4 Any specimen of low times the organization failed, according to the following principles to determine.
a) because of cracks, bright grains, inclusions and other metallurgical defects failed, the sentence of the batch of bars failed. By agreement between the supply and demand, allowed by
The supplier will be allowed to inspect the bars one by one and judge them one by one.
b) due to the formation of layers, shrinkage, coarse crystal ring failed, allowed to cut off a section from the end of the bar extrusion to repeat the test, until qualified, then the batch of
Other bars shall be subject to inspection of the maximum length of the distribution of the above defects of the bar cut tail or root by root inspection, root by root judgment.
8.5.5 Any bar of the appearance of quality failed, the sentence of the bar failed.
9 signs, packaging, transportation, storage and quality certification
10 order form (or contract) content
