Content is king. Adding new, unique and relevant content to your website is one of the most cost-effective ways to increase traffic to your website. There is absolutely no downside to adding the free articles to your blog.
In fact, over time you will see significant increases to your website traffic as the size of your site grows.
The goal of a blog should be to basically turn your website into an encyclopedia of all things related to your services. Every blog articles simply increases the ways in which someone can find your site via a search engine like Google.