IPC-A-600H-2010 中文版 印制板的可接受性 (1).pdf - 第30页
Crazing: An internal condition occurring in the laminated base material in which the fibers within the yarn are separated. This can occur at the weave intersections or along the length of the yarn. This condition manifes…
Measling: Measling manifests itself in the form of discrete white squares or ‘‘crosses’’ below the surface of the base material, and is usu-
ally related to thermally induced stress. Measles are subsurface phenomena that have been found in new laminated materials and in every
board type made from woven fiber reinforced laminates at one time or another. Since measles are strictly subsurface phenomena and occur
as a separation of fiber bundles at fiber bundle intersections, their apparent positions relative to surface conductors have no significance.
⽩斑：白斑表现为基材表面下不连续的白色方块或“十字”纹，其形成通常与热应力有关。白斑是一种基材表面下现象，在新层
压基材上和织物增强层压板制成的各种板上都时有发生。由于白斑绝对出现在表面下并且是在纤维束交叉处发生分离而出现，因
此，其出现的位置相对于表面导体毫无意义。
Target - Class 1,2,3（⽬标条件 - 1,2,3级）
• No evidence of measling.
• 无白斑迹象。
Acceptable - Class 1,2（可接受条件 - 1,2级）
• The criteria for measling is that the printed board is functional.
• 对白斑的准则是印制板仍具有功能。
Process Indicator - Class 3（制程警⽰ - 3级）
• Measled areas in laminate substrates exceed 50% of the physical spacing
between noncommon conductors.
• 层压基材中白斑面积超过非公共导体之间实际间距的50%。
Note: Measling is an internal condition which does not propagate as a
result of thermal testing that replicates future assembly processes and has not
been conclusively shown to be a catalyst for CAF growth. Delamination is an
internal condition which may propagate under thermal stress and may be a
catalyst for CAF growth. The IPC-9691 user's guide for CAF resistance test-
ing and IPC-TM-650, Method 2.6.25, provide additional information for
determining laminate performance regarding CAF growth. Users who wish to
incorporate additional criteria for measle conditions may consider incorporat-
ing the provisions of IPC-6012, Class 3A which does not allow measles.
注：白斑是层压板中的一种内部现象，不会由于模拟组装制程的热应力
测试而扩展，同时也无明确结论显示它是阳极导电丝（CAF）生长的诱
因。分层是一种在热应力作用下可能扩展的内部现象，同时也可能是
CAF生长的诱因。关于耐CAF测试，IPC-9691用户指南和IPC-TM-650测
试方法2.6.25均提供了确定层压板 CAF生长性能的其他信息。希望加
入白斑状况其他要求的用户可考虑纳入不允许白斑出现的3A级要求。
Note: Measles are observed from the surface. Cross-sections are for illustration purposes.
注：
白斑可从表面观察。剖面图仅用于图示。
图231b
注：此图仅⽤作说明状况，并不要求做显微剖切评价。
图231d
图231a
图231c
2.3 BASE MATERIAL SUBSURFACE（基材表⾯下）
2.3.1 Measling（⽩斑）
21IPC-A-600H-2010 2010年4月
Crazing: An internal condition occurring in the laminated base material in which the fibers within the yarn are separated. This can occur at
the weave intersections or along the length of the yarn. This condition manifests itself in the form of connected white spots or ‘‘crosses’’
below the surface of the base material, and is usually related to mechanically induced stress. When the crosses are connected the condition is
evaluated as follows:
微裂纹：层压基材内纤维发生分离的一种内部状况。微裂纹可在纤维交织处或沿纤维丝长度方向出现。微裂纹状况表现为基材表
面下相连的白点或“十字纹”，通常与机械应力有关。当十字纹相互连接时，微裂纹状况评定如下：
Target Condition - Class 1,2,3（⽬标条件 - 1,2,3级）
• No evidence of crazing.
• 无微裂纹迹象。
Acceptable - Class 2,3（可接受条件 - 2,3级）
• The imperfection does not reduce the conductor spacing below
the minimum.
• The distance of crazing does not span more than 50% of the dis-
tance between adjacent conductive patterns that are not electri-
cally common.
• No propagation as a result of thermal testing that replicates the
manufacturing process.
• Crazing at the edge of the printed board does not reduce the mini-
mum distance between printed board edge and conductive pat-
tern; or more than 2.5 mm [0.0984 in] if not specified.
• 瑕疵未使导体间距减少至低于最小导体间距。
• 微裂 纹 的 跨 距 不大于相邻非电气共接导电图形之间距离的
50%。
• 没有因为模拟制造过程的热测试而扩大。
• 印制板边的微裂纹未减少板边与导电图形间的最小距离，若
未规定最小距离时，则微裂纹不大于2.5mm[0.0984in]。
Note: Crazing is observed from the surface. Cross-sections are for illustration purposes only.
注：
微裂纹可从表面观察。剖面图仅用于图示。
图232b
注：此图仅⽤作说明状况，并不要求做显微剖切评价。
图232d
图232a
图232c
2.3 BASE MATERIAL SUBSURFACE（基材表⾯下）
2.3.2 Crazing（微裂纹）
22 IPC-A-600H-20102010年4月
Acceptable - Class 1（可接受条件 - 1级）
• The imperfection does not reduce the conductor spacing below
the minimum.
• No propagation as a result of thermal testing that replicates the
manufacturing process.
• Crazing at the edge of the printed board does not reduce the mini-
mum distance between printed board edge and conductive pat-
tern; or more than 2.5 mm [0.0984 in] if not specified.
• 瑕疵未使导体间距减少至低于最小导体间距。
• 没有由于模拟制造过程的热测试而扩大。
• 印制板边的微裂纹未减少板边与导电图形间的最小距离，若
未规定最小距离时，则微裂纹不大于2.5mm[0.0984in]。
Nonconforming - Class 1,2,3（不符合条件 - 1,2,3级）
• Defects either do not meet or exceed above criteria.
• 缺陷不符合或超出上述要求。
图232e
2.3 BASE MATERIAL SUBSURFACE（基材表⾯下）
2.3.2 Crazing (cont.)（微裂纹（续））
23IPC-A-600H-2010 2010年4月