500小时中性盐雾试验后，样品无锈迹明显变化的翻译：After 500 hour neutral salt spray testing, samples of rust-free clear change 什么意思？中文翻译英文，英文翻译中文，怎么说？

青云英语翻译

500 hours neutral salt spray test, rust no significant change in the sample

After 500 hour neutral salt spray testing, samples of rust-free clear change

After 500 hour neutral salt-fog tests, the sample does not have the rusty stain obvious change

Of the 500 hours salt spray test samples, there is no rust after apparent change

After 500 hour neutral salt spray testing, samples of rust-free clear change