corroded wepaons have a minus to attack and dmg

Wood can act as a source of water for corrosion processes. ‘Safe’ limits are set in the Museum at 40%-45% RH for unstable iron and bronzes containing chlorides and 55% RH for good quality iron and bronzes with stable patinas. At lower humidities, however, the rate of corrosion progressively diminishes. For most corrosion processes the presence of moisture and oxygen at the metal surface is essential although the atmosphere need not be water saturated. (Museum no IM 69-1914) (click image for larger version)Ĭorrosion is essentially a process of oxidation. The object is a 19th Century bronze statue of Nandi, the Kneeling bull of Shiva. Wood also contains small amounts of non-structural organic materials, collectively called extractives, and significant quantities of water. The structural components of wood are complex organic molecules - cellulose, hemicellulose and lignin. This article briefly reviews ways in which wood may contribute to the corrosion of metal objects. Damage to metal objects in the Burrell Collection was reported during the day on Storage at the UKIC conference, Restoration '91. This has long been known but is still sometimes forgotten. Such interactions can occur through direct contact of metal fastenings and fittings with wood or indirectly, through the environment when metal objects are transported, stored, or displayed in wooden containers. However, interactions between certain metals and woods can take place under adverse conditions, or as a result of using unsuitable materials.

Wood and metal are used together for so many purposes that they are usually regarded as highly compatible materials. The reactions for lead may be: (click image for larger version)

Corroded wepaons have a minus to attack and dmg