The fracture behavior of adhesively bonded joints is of interest in a variety of industrial, natural and biological applications. This effort re-examines literature data with an emphasis on thin bonds and their relation to delamination resistance. Brittle, ductile and particulate epoxy adhesives were considered with the bond thickness t varying from 1 to 1000 μm. The results shed new light on some basic morphological and fracture characteristics. The fracture energy is affected by numerous factors including adhesive material, bond thickness and loading mode. Shear fracture generally begins with growth of tensile microcracks ahead of the crack tip and continues with coalescence of these cracks along the interface in a process accompanied by extensive plasticity. With G_IIC ≈ G_IIIC, mixed-mode fracture can be described by tensile (G_I) vs. shearing (G_SC) ERR. For thin bonds (t < ≈ 10 μm), G_IC ≈ constant, G_SC increases virtually linearly with t, and G_SC ≈ G_IC = G₀ when t → 0. These traits result in a closed-form expression for G_C given in terms of basic material properties. The thin-bond results provide cost-effective means for predicting interlaminar fracture energy G_IC or G_IIC and elucidating an interleaf thickness for optimal delamination resistance. A detailed examination of published data reveals that within certain limitations, the mixed-mode fracture envelope is independent of t or material type. This finding may help develop analytical fracture models for practical use.

粘合接头的断裂行为在各种工业，天然和生物学应用中都很重要。这项工作重新检查了文献数据，重点是薄键及其与抗脱层性的关系。考虑了脆性，易延展性和颗粒状环氧粘合剂，其粘合厚度t在1至1000μm之间变化。结果为一些基本的形态和断裂特征提供了新的启示。断裂能受多种因素影响，包括粘合剂材料，粘结厚度和加载方式。剪切断裂通常始于在裂纹尖端之前的拉伸微裂纹的生长，并在伴随着广泛可塑性的过程中随着沿界面的这些裂纹的聚结而继续。与G _IIC ≈  ģ _IIIC，混合模式断裂可通过拉伸（被描述ģ_我）与剪切（ģ _SC）ERR。对于薄键（吨<≈10微米），G ^ _IC  ≈恒定，ģ _SC几乎线性地增加吨，和G ^ _SC  ≈  ģ _IC  =  g ^ ₀时吨 →0。这些性状导致对于一个封闭形式的表达式G ^ _{C ^}在基本材料特性方面给出。薄键结果为预测层间断裂能G提供了经济有效的手段_IC或G _IIC并阐明插页厚度以获得最佳的抗分层性。对已发表数据的详细检查表明，在一定限制下，混合模式裂缝包络与t或材料类型无关。这一发现可能有助于开发实用的分析裂缝模型。