GB/T 38940-2020Precision expansion alloys for sealing to silicon and silicon components (English PDF)

4.1

Alloy materials can be divided into.

a) Soft state (S);

b) Hard state (H).

4.2

Alloy materials can be divided into.

a) Cold drawn (WCD);

b) Cold drawn polishing (WCDG);

c) Hot rolled (forged) state (WH).

6.1 Grade and chemical composition

The alloy grade and chemical composition (melting analysis and finished product analysis) should meet the requirements of Table 1.In the case of meeting the requirements of this standard,

The chemical composition of nickel, cobalt, niobium, and copper is allowed to deviate from the regulations in Table 1, but should meet the regulations in Table 3 of GB/T 222-2006.

6.2 Smelting method

Unless otherwise specified in the contract, the alloy should be smelted by vacuum induction furnace and vacuum induction electroslag remelting.

6.3 Delivery status

6.3.1

The bars are delivered in cold drawn, cold drawn and polished or hot rolled (forged) state. If there are requirements for the surface condition of the hot rolled (forged) material, it shall be included in the contract

Specify.

6.3.2

Flat products are delivered in hot rolled (forged) state.

6.3.3

The delivery status of wires, strips, foils and pipes should meet the requirements of Table 2.

6.3.4

After negotiation between the supplier and the buyer, alloy materials in other delivery states are available.

6.4 Average linear expansion coefficient

After the sample is treated according to the heat treatment system recommended in Table 3, the average linear expansion coefficient of the alloy material should meet the requirements of Table 3.Classic of alloy materials

Type performance see Appendix A.

6.5 Metallographic structure

6.5.1 Phase transition

After 4J330 alloy material is treated according to the heat treatment system specified in Table 3, the phase transition temperature of gamma->alpha should be below -60°C. For diameter, edge

For bars with a length or thickness greater than 25mm, local phase changes are allowed, but the proportion of phase changes should not exceed 5% of the test section.

6.5.2 Grain size

6.5.2.1

The average grain size of deep-drawn strips should be level 7 or finer, and grains larger than level 7 are allowed to exist, but should not exceed the total area

Of 10%.

6.5.2.2

The average grain size of the alloy bars and flats in the delivery state should be level 3 or finer. This test is not required when the phase transformation test is qualified.

6.6 Air tightness

According to the requirements of the buyer, the bar with a diameter or side length of not less than 15mm can be tested for airtightness and there should be no air leakage.

6.7 Surface quality

The surface quality of the alloy material should meet the relevant regulations of GB/T 14985-2007.

6.8 Ultrasonic testing

6.8.1

Bars with a diameter and side length of not less than 12mm shall be subjected to ultrasonic testing, and the qualification level shall comply with GB/T 4162-2008 Class A

Claim.

6.8.2

GB/T 2970 can be used for ultrasonic testing of flat materials and plates, and the qualified level shall be negotiated by the supplier and the buyer and indicated in the contract.

6.8.3

The pipes can be tested by GB/T 5777 ultrasonic testing, or by other general non-destructive testing methods. Qualification level is determined by supply and demand

Both parties negotiated and indicated in the contract. If there are disputes caused by different methods, GB/T 5777 shall be the basis for arbitration.

6.9 Special requirements

After negotiation between the supplier and the buyer and indicated in the contract, alloy materials meeting other special requirements can be supplied.

7.1

The inspection items and test methods of alloy materials should meet the requirements of Table 4.

a The air tightness inspection is carried out by the buyer, and the thickness of the inspected sample should be indicated in the contract, otherwise the inspection shall be carried out according to sample A specified in YB/T 5321-2006.

7.2

The chemical composition analysis of the alloy is in accordance with GB/T 223.79, GB/T 11170, GB/T 20123, GB/T 20125, GB/T 22368,

GB/T 38939 or general test methods are used for analysis, but GB/T 223.5, GB/T 223.19, GB/T 223.20,

GB/T 223.25, GB/T 223.40, GB/T 223.60, GB/T 223.62, GB/T 223.64, GB/T 223.85, GB/T 223.86

The relevant regulations are carried out.

8.1 Inspection and acceptance

The inspection and acceptance of alloy materials are carried out by the supplier's technical quality supervision department. The purchaser has the right to inspect and accept according to the standard. airtight

The sex test is carried out by the purchaser.

8.2 Batching rules

Alloy materials should be submitted for inspection and acceptance in batches. Each batch should be made of the same alloy grade, the same heat number, the same processing method, the same size, and the same

Delivery status and composition of alloy materials with the same heat treatment system.

8.3 Sampling quantity and sampling location

The sampling quantity and sampling location of alloy materials should meet the requirements of Table 4.

8.4 Re-inspection and judgment rules

The re-inspection and determination rules of alloy materials should comply with the relevant regulations of GB/T 14985-2007.