对于结构钛合金，通过各种试验程序测量的断裂韧性特性的解释，用于解决一般工程问题。从断裂力学理论发展而来的分析程序用于工程断裂韧性试验的定量解释。工程试验程序的简单性，加上断裂力学理论的分析能力，使钛合金的失效安全设计程序在涵盖所有强度水平的范围内取得了重大进展。 解释程序是从KIc与动态撕裂（DT）和夏比V型缺口（Cv）能量的相关性发展而来的。为钛合金开发了最佳材料趋势线（OMTL）图，该图总结了所有DT断裂韧性数据，并根据KIc和Cv相关图进行了额外索引。 OMTL极限曲线显示了强度等级的最佳和通常预期的材料等级。 1英寸和3英寸断裂的缺陷尺寸应力计算。厚截面以iso缺陷深度线的形式覆盖在OMTL图上。将KIc/σys比值线与iso缺陷深度线进行索引，并形成KIc/σys比值分析图（RAD）。RAD提供了裂纹尺寸/应力条件的简化、通用工程解释。 一些主要钛合金的一般断裂韧度特征由RAD中的区域简单定义。这些区域的概要提供了对每一类钛合金潜力的一般理解。

Interpretations of fracture toughness characteristics, as measured by various test procedures, for solutions of general engineering problems, are presented for structural titanium alloys. Analytical procedures evolved from fracture mechanics theory are used for quantitative interpretations of engineering fracture toughness tests. The procedural simplicity of the engineering tests coupled with the analytical capabilities of fracture mechanics theory provides for a significant advancement in failure-safe design procedures for titanium alloys covering the full range of strength levels. Interpretative procedures are evolved from correlations of KIc with Dynamic Tear (DT) and Charpy-V notch (Cv) energy. An Optimum Material Trend Line (OMTL) diagram is developed for titanium alloys which summarizes all the DT fracture toughness data and is additionally indexed according to the KIc and Cv, correlation plots. OMTL limit curves are shown for the best and normally expected grades of material for the strength level. Flaw size-stress calculations for fracture of 1- and 3-in. thick sections are overlaid to the OMTL diagram in the form of iso-flaw depth lines. KIc/σys ratio lines are indexed to the iso-flaw depth lines and a KIc/σys Ratio Analysis Diagram (RAD) is evolved. The RAD provides for a simplified, general engineering interpretation of flaw size/stress conditions for fracture. The general fracture toughness characteristics of some principal titanium alloys are simply defined by zones in the RAD. A compendium of such zones provides a general understanding of the potentials for each generic class of titanium alloys.