{"id":"wpc-foundations30-article-020-en","slug":"wpc-mechanical-properties-strength-modulus-impact","locale":"en","url":"https://woodplasticcomposite.net/guides/wpc-mechanical-properties-strength-modulus-impact/","title":"Reading WPC mechanical data: strength, stiffness and impact","answer":"Strength describes resistance to a defined failure condition; stiffness describes resistance to deformation. A strong small specimen does not automatically establish a suitable structural profile.","author":"NFC & WPC Knowledge Reference","faqIds":[],"tagIds":[],"noindex":false,"related":["wpc-foundations30-article-021-en","wpc-foundations30-article-022-en","wpc-foundations30-article-023-en"],"version":1,"modified":"2026-10-16","reviewer":"","sections":[{"id":"translate-the-terminology","text":"Tensile tests load a specimen in tension. Flexural tests bend it. MOR commonly denotes modulus of rupture, a bending-strength measure, while MOE denotes modulus of elasticity, a stiffness measure. Compression describes another loading condition. Impact tests such as Izod and Charpy introduce their own specimen and loading arrangements.\n\nSee the comparison table below for translate the terminology.","heading":"Translate the terminology","references":[],"url":"https://woodplasticcomposite.net/guides/wpc-mechanical-properties-strength-modulus-impact/#translate-the-terminology"},{"id":"do-not-merge-impact-numbers","text":"Wood/PP research found different particle-size trends for notched and unnotched impact. This illustrates why impact results require their exact test description. An instrumented-impact study of kenaf/PP provides another example of investigating impact behaviour in a specific composite system. [R20,R48]","heading":"Do not merge impact numbers","references":[],"url":"https://woodplasticcomposite.net/guides/wpc-mechanical-properties-strength-modulus-impact/#do-not-merge-impact-numbers"},{"id":"specify-the-evidence-chain","text":"The EN 15534 family connects compound and product characterization with particular end uses. Its existence does not mean that citing the standard number proves compliance. \n\nFor a public walkway, request the tested board identity, support arrangement and relevant acceptance criteria. For a new compound, request the number of specimens and variability as well as the mean. Keep initial laboratory properties separate from conditioned values and design values.\n\nThis approach lets architects compare products on evidence rather than a single impressive number selected from a datasheet.","heading":"Specify the evidence chain","references":[1],"url":"https://woodplasticcomposite.net/guides/wpc-mechanical-properties-strength-modulus-impact/#specify-the-evidence-chain"},{"id":"evidence-scope","text":"[1] Official standards catalogue; scopes, not full normative text.\n\n[2] Experimental study; official abstract.\n\n[3] Experimental study.","heading":"Evidence and source scope","references":[1,2,3],"url":"https://woodplasticcomposite.net/guides/wpc-mechanical-properties-strength-modulus-impact/#evidence-scope"}],"seoTitle":"Reading WPC mechanical data: strength, stiffness and impact","topicIds":[],"published":"2026-10-16","tableText":"Reported property | Essential comparison detail\nTensile strength | Specimen geometry, direction and conditioning\nFlexural strength or MOR | Span, section and test procedure\nFlexural modulus or MOE | Calculation method and conditions\nImpact result | Test type, notch and units","takeaways":"","aiAssisted":true,"categoryId":"wpc-foundations30-category-performance-testing","reviewedAt":"","change_note":"Converted from the referenced English foundations collection. General technical information and editorial specification guidance; not product certification.","description":"Understand tensile and flexural strength, MOR, MOE, compression and impact tests, and learn how to compare WPC data without misleading shortcuts.","heroImageId":"","referenceIds":["wpc-foundations30-ref-r02","wpc-foundations30-ref-r20","wpc-foundations30-ref-r48"],"review_status":"AI-assisted English article. Human technical review has not been recorded.","table_caption":"Similar property names can conceal materially different test conditions.","seoDescription":"Understand tensile and flexural strength, MOR, MOE, compression and impact tests, and learn how to compare WPC data without misleading shortcuts.","translationGroup":"wpc-foundations30-020-2026","references":[{"url":"https://landingpage.bsigroup.com/LandingPage/Series?UPI=BS+EN+15534","type":"web","title":"EN 15534 standards series; BSI","noindex":false,"accessed":"2026-10-15","seoTitle":"EN 15534 standards series; BSI","publisher":"landingpage.bsigroup.com","description":"Official standards catalogue; scopes, not full normative text","seoDescription":"Official standards catalogue; scopes, not full normative text"},{"url":"https://research.fs.usda.gov/treesearch/8558","type":"web","title":"Effects of wood fiber characteristics on mechanical properties of wood/polypropylene composites; Stark and Rowlands","noindex":false,"accessed":"2026-10-15","seoTitle":"Effects of wood fiber characteristics on mechanical properties of wood/polypropylene composites; Stark and Rowlands","publisher":"research.fs.usda.gov","description":"Experimental study; official abstract","seoDescription":"Experimental study; official abstract"},{"url":"https://research.fs.usda.gov/download/treesearch/32710.pdf","type":"web","title":"Instrumented Impact Testing of Kenaf Fiber Reinforced Polypropylene Composites","noindex":false,"accessed":"2026-10-15","seoTitle":"Instrumented Impact Testing of Kenaf Fiber Reinforced Polypropylene Composites","publisher":"research.fs.usda.gov","description":"Experimental study","seoDescription":"Experimental study"}],"faqs":[]}