MIL-STD-202H.pdf - 第166页

MI L - S TD - 202 - 210 4.1.4 Mount ing board. A m ou nt i ng boar d, i n a c c or dan c e w i t h N E M A gr ade F R - 4 of I P C 4 101 , 9 squar e inches (i.e., 3 x 3, 1 x 9, etc.), mi n i m u m ar e a, . 0 62 i nc h ±…

MIL-STD-202-210

METHOD 210

RESISTANCE TO SOLDERING HEAT

1. SCOPE

1.1 Purpose. This test is performed to determine whether wire and other component parts can withstand the

effects of the heat to which they will be subjected during the soldering process (solder iron, solder dip, solder wave,

or solder reflow). The heat can be either conducted heat through the termination into the component part, or radiant

heat from the solder bath when in close proximity to the body of the component part, or both. The solder dip method

is used as a reasonably close simulation of the conditions encountered in wave soldering, in regard to radiated and

conducted heat. This test also is intended to evaluate the impact of reflow techniques to which components may be

exposed. The heat of soldering can cause solder reflow which may affect the electrical characteristics of the

component part and may cause mechanical damage to the materials making up the part, such as loosening of

terminations or windings, softening of insulation, opening of solder seals, and weakening of mechanical joints.

2. APPLICABLE DOCUMENTS

2.1 Non-Government publications. The following documents form a part of this document to the extent specified

herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract.

ASSOCIATION CONNECTING ELECTRONIC INDUSTRIES (IPC)

IPC 4101 - Specification For Base Materials For Rigid and Multilayer Printed Boards

J-STD-004 - Requirements For Soldering Fluxes

J-STD-005 - Requirements For Soldering Pastes

J-STD-006 - Requirements For Electronic Grade Solder Alloys and Fluxed and Non-Fluxed Solid Solders For

Electronic Soldering Applications

(Copies of these documents are available online at www.IPC.org)

3. DEFINTIONS

This section not applicable to this standard.

4. GENERAL REQUIREMENTS

4.1 Apparatus

4.1.1 Solder pot. A static solder pot, of sufficient size to accommodate the mounting board (see 4.1.4) and to

Immerse the terminations to the depth specified for the solder dip (without touching the bottom of the pot), shall be

used. This apparatus shall be capable of maintaining the solder at the temperature specified. The solder bath

temperature shall be measured in the center of the pot at a depth of at least .500 inch (12.7 mm), but no deeper than

1 inch (25.4 mm) below the surface of the solder.

4.1.2 Heat sinks or shielding. The use of heat sinks or shielding is prohibited except when it is a part of the

component. When applicable, heat sinks or shielding shall be specified in the individual specification, including all of

the details, such as materials, dimensions, method of attachment, and location of the necessary protection.

4.1.3 Fixtures. Fixtures, when required, shall be made of a non-solderable material designed so that they will

make minimum contact (i.e., minimum heat sink) with the component. Further, they shall not place undue stress on

the component when fixtured.

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MIL-STD-202-210

4.1.4 Mounting board. A mounting board, in accordance with NEMA grade FR-4 of IPC 4101

, 9 square inches

(i.e., 3 x 3, 1 x 9, etc.), minimum area, .062 inch ±.0075 inch (1.57 mm ±.191 mm) thick, shall be used, unless

otherwise specified. Component lead holes shall be drilled such that the diametrical clearance between the hole and

component terminals shall not exceed .015 inch (0.38 mm). Metal eyelets or feed-throughs shall not be used.

Surface mount boards, when specified in the individual specification, shall have pads of sufficient size and number to

accommodate the component being tested.

4.1.5 Solder iron. A solder iron, capable of maintaining a temperature of 350°C ±10°C, shall be used.

4.1.6 Reflow chambers. The reflow chambers or equivalent (Vapor Phase Reflow (VPR) chamber, Infrared Reflow

(IRR) oven, air circulating oven, etc.) shall be of sufficient size to accommodate the mounting board and components

to be tested. The chamber shall be capable of generating the specified heating rate, temperatures, and

environments.

4.1.7 Temperature measurement. Low mass thermocouples that do not affect the heating rate of the sample shall

be used. A temperature recording device is recommended. The equipment shall be capable of maintaining an

accuracy of ±1°C at the temperature range of interest.

4.2. Materials.

4.2.1 Solder. The solder or solder paste shall be tin-lead alloy with a nominal tin content of 50 percent to 70

percent in accordance with J-STD-006, “Requirements for Electronic Grade Solder Alloys and Fluxed and Non-

Fluxed Solid Solders for Electronic Soldering Applications” or J-STD-005, “Requirements for Soldering Pastes”.

When specified in the individual specification, other solders can be used provided they are molten at the specified

temperature.

4.2.2 Flux. When flux is used, it shall conform to type A of J-STD-004

, “Requirements for Soldering Fluxes”, or as

specified in the individual specification.

4.2.3 VPR fluid. A perfluorocarbon fluid that has a boiling point of 215°C shall be used.

4.3 Procedure.

4.3.1 Special preparation of specimens. Any special preparation of specimens prior to testing shall be as specified

in the individual specification. This could include specific instructions such as bending or any other relocation of

terminations, cleaning, application of flux, pretinning, or attachment of heat sinks or protective shielding (see 4.1.2),

prior to the solder immersion.

4.3.2 Preparation of solder bath. The molten solder shall be agitated to assure that the temperature is uniform.

The surface of the solder shall be kept clean and bright.

4.3.3 Application of flux. When flux is used, the terminations to be tested shall be immersed in the flux (see 4.2.2),

which is at room ambient temperature, to the depth specified for the solder dip. The duration of the immersion shall

be from 5 seconds to 10 seconds.

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MIL-STD-202-210

4.3.4 Test conditions. Unless otherwise specified in the individual specification, the test shall be performed on all

solder terminations attached to the component part. There are six types of soldering techniques covered by these

test conditions. The test conditions are outlined below and in table I.

Test condition A: Solder iron - Hand soldering of solder cups, through hole components, tab and post

terminations, solder eyelet terminations.

Test condition B: Solder dip - Simulates hot solder dipping (tinning) of leaded components.

Test condition C: Wave solder - Simulates wave solder of topside board mount product.

Test condition D: Wave solder - Simulates wave solder of bottomside board mount product.

Test condition H: VPR - VPR environment without preheat.

Test conditions I, J, K: Infrared/Convection reflow - Simulates IRR, natural convection, and

forced air convection reflow environments.

4.3.4.1 Test condition A: Solder iron.

a. When testing a solder cup, tab and post termination, or solder eyelet termination, the applicable wire size,

properly prepared for the solder termination, shall be attached in the appropriate manner.

When testing a board mount component, the component shall be placed on a mounting board (see 4.1.4).

b. When specified, the components shall be fluxed (see 4.3.3).

c. Unless otherwise specified, a solder iron in accordance with 4.1.5 shall be used.

d. The solder iron shall be heated to 350°C ±10°C and applied to the termination for a duration of 4 seconds to 5

seconds as specified in table I. The solder and iron shall be applied to the area of the assembly closest to

the component body that the product is likely to experience. For surface mount components, the iron shall be

placed on the pad only.

e. Remove the iron and allow the component to cool and stabilize at room ambient conditions. If flux was used,

the component shall be cleaned using an appropriate cleaning solution.

f. The component shall be visually examined under 10X magnification.

4.3.4.2 Test condition B: Solder dip.

a. Place the component in an appropriate fixture (see 4.1.3).

b. When specified, the leads shall be fluxed (see 4.3.3).

c. The specific combination of temperature, immersion and emersion rate, immersion duration, and number of

heats shall be as specified in table I. Unless otherwise specified, terminations shall be immersed to within

.050 inch (1.27 mm) of the component body. Terminations shall be immersed simultaneously, if the geometry

of the component permits.

d. After the solder dip, the component shall be allowed to cool and stabilize at room ambient conditions. If flux

was used, the component shall be cleaned using an appropriate cleaning solution.

e. The component shall be visually examined under 10X magnification.

北测（上海）电子科技有限公司

联系方式：xuyj@beice-sh.com 13917165676